FIRST IMPRESSIONS: First Impressions: The nicely styled diaphragm-type first stage has a swivelling port for the medium-pressure hose to take full advantage of its ambidextrous second stage. The other six ports are angled to give a good hose routeing, including two hp ports facing downwards. Its very compact second stage was the nicest of those with side exhausts compared here and metal inserts act as a heat-sink for cold fresh-water use. We thought it looked very sleek.
IN THE WATER:
"It was surprisingly dry (for a side-exhaust regulator) in all positions. The purge button was difficult to use but it did the job. It gave a perfectly acceptable breathing effort and it did not free-flow when out of the mouth."
"The inhalation was excellent, with little apparent effort needed but I found that one eye was always obscured by exhaust bubbles. I felt the purge button was too hard to operate. Breathing felt effortless."
"It was a bit noisy, which was disconcerting, but it was easily the best of the side-exhaust models tested. Inhaling provided a squirt of air rather than a flood. The purge proved difficult and I found it needed two hands to use"
"I really wanted to like it because it looked excellent but I found that one eye was constantly obscured by exhaust bubbles. The flow of air from the purge seemed weak, although it was hard to push on to make work. Although the breathing was acceptably good, I'm afraid I was disappointed overall."
INVERTED: Dry.
SECOND-STAGE ASSEMBLY: We could not disassemble this regulator without the use of a jeweller's screwdriver, so it proved unsuitable for dismantling in the field.
ANSTI RESULT: An initial flutter was followed by increasing effort and then some positive pressure indicated a less-than-smooth performance. Work of breathing = 1.57 joules/litre.

FIRST IMPRESSIONS: A very chunky-looking diaphragm-design first stage, seriously over-engineered and very heavy. It gave excellent hose routeing with two hp and four mp ports. The metal second stage has good heat-sink properties for cold fresh water but is starting to look dated. We liked the fact that the venturi bypass tube design means no additional adjustments are needed but did not like what seemed a tiny mouthpiece for such a substantial item.
IN THE WATER:
"Not the best of the test but perfectly acceptable. I had no serious issues with it and no problems. It worked at any angle without giving me a wet breathe. There was no exhaust bubble problem, although I thought the short stubby mouthpiece rather feeble."
"I'd use one again without a problem. That said, when I turned face-up it tightened up considerably and I could hear the first-stage valve opening. It burst into free-flow when out of my mouth at almost any depth. It got a bit squeaky towards the end of the week."
"Very good. It responded to demand at all times. It never seemed to over-estimate what you needed. If you heaved, it gave you loads. The purge was excellent and sensitive with a good range."
"It felt natural, like I was breathing in a cathedral. It was easy and dry but it free-flowed too easily when out of the mouth. Face-up, it seemed slightly damp."
INVERTED: Excellent. Very dry.
SECOND-STAGE ASSEMBLY: We needed a screwdriver to remove the front
ANSTI RESULT:A large initial cracking pressure was followed by fairly even inhalation. Work of breathing = 1.45 joules/litre.

FIRST IMPRESSIONS: A compact environmentally sealed diaphragm-design first stage with a removable sealing cap and an attractive and hard-wearing rubber cover. It has four mp and two hp ports with distinctive port plugs. It has an attractive black plastic and metal trim second stage with venturi ± and BRA, and with a heat exchanger for coldwater use and a good-width exhaust-T. Its finish began to look a little tired after five days. It comes with a Comfobite mouthpiece.
IN THE WATER:
"Very smooth. An exceptionally nice breathe. One of the best. It proved difficult to make it free-flow. However, I preferred to use the (Comfobite) mouthpiece fitted upside-down."
"Absolutely excellent, even supreme! Probably my favourite. Its purge button was excellent and very controllable.."
"An easy breathe at any depth, but the Bugs Bunny mouthpiece takes some getting used to. It was not as good as the best but, otherwise, I was very happy with it."
"Generally comfortable to breathe from but I felt the mouthpiece pushed it too far forward. I liked it otherwise. I seemed to get a lot of air. The venturi ± switch seemed to make no detectable difference."
INVERTED: Very dry.
SECOND-STAGE ASSEMBLY: It seemed that we could not disassemble it without a special tool.
ANSTI RESULT:An initial cracking effort was followed by some positive pressure, resulting in an extremely low work of breathing of only 0.7 joules/litre.

FIRST IMPRESSIONS: A distinctive diaphragm-design first stage reminiscent of that of the older Aqua-lung Titan with an environmental sealing kit attached. The second stage has titanium inserts which make it look attractive and act as a heat-sink but it seems very large when compared with most of the others. It has a venturi ± and BRA and the exhaust-T was a nice size but poorly attached by means of a single cross-head screw.
IN THE WATER:
"Not "wow", but very nice. It gave a stable supply of air when asked. The purge seemed very polite in comparison to some others. I felt the venturi ± switch was a complete waste of time and the mouthpiece was a bit basic for such an expensive bit of kit."
"Quite nice but not as good as some of the others. I felt I had to consciously draw in each breath. The purge was effective but not strong. This reg was difficult to get to free-flow out of the mouth. The BRA made a difference at depth. The mouthpiece felt rather inadequate."
"Although it gave a perfectly adequate supply of air it came in a thin squirt rather than a flood like some others. It was not unpleasant but different. It has a good sensitive purge control and there was no problem when face-up."
"I liked this regulator. I felt very comfortable with it, though I noticed a little effort at times. The venturi adjustment made no difference, though the BRA did stop it free-flowing when out of the mouth at depth. Exhaled bubbles seemed to be everywhere. Face-up, I detected a small ingress of water."
INVERTED: Slightly wet but tolerable.
SECOND-STAGE ASSEMBLY:It should have been easy to disassemble in the field but had been done up too tightly.
ANSTI RESULT:One of the lesser performers in this price-range, this regulator seemed sensitive to tank pressure. Work of breathing = 1.84 joules/litre.

FIRST IMPRESSIONS: A piston-type turret first stage with five mp and two hp ports which gives superb hose routeing, but it has evolved from earlier models into what now looks a rather fussy design. It has both a venturi ± and a BRA and a good mouthpiece with a re-useable clip. The whole effect looks expensive and well-finished.
IN THE WATER:
"Although it seemed on the edge of free-flowing at all times, it was one of the best regulators I have ever breathed from. It was almost as good as putting your head up out of the water to breathe. The venturi ± control seemed totally ineffective. The mouthpiece was really comfortable. One of my favourites."
"A delight to breathe from. The purge was very controllable although the other controls seemed very ineffective. It was very light in the mouth. Its excellent breathing gave a calming effect all of its own. I would definitely buy one."
"A very nice breathe, very natural and smooth although the small exhaust-T meant exhaust bubbles interfered with my vision. Neither adjustment knob seemed to make any detectable difference."
"A very pleasant breathe, although the exhaust bubbles were a bit distracting. Nice in comparison to some others but for me it was not the best tested."
INVERTED: Virtually dry in nearly all positions.
SECOND-STAGE ASSEMBLY:We do not advise readers to try to take the second stage apart for cleaning outside a workshop because it proved so difficult to put back together.
ANSTI RESULT:A very low if slightly less than totally smooth inhalation effort. Work of breathing = 0.89 joules/litre.

FIRST IMPRESSIONS: An environmentally dry-sealed, diaphragm-design first stage with four mp and two hp ports and very good hose routeing, but not as good as the ATX200. The second stage was identical to that of the ATX200. We felt that in some ways it was a bit of a false start for Apeks, improving on the TX50 but not going as far as the ATX200. This model comes with a choice of standard or Comfobite mouthpieces.
IN THE WATER:
"I could not detect a difference between this and the ATX200. With the BRA knob cranked right open it gave a near-perfect breathe. A very nice regulator that was spoiled only by its exhaust bubbles passing before my eyes. I preferred to use the (Comfobite) mouthpiece upside-down."
"A very good delivery with excellent control. In fact, excellent at every angle apart from inverted. A very nice regulator, spoiled only by a too-small exhaust-T. Otherwise, I felt it was very much like a TX50. Very good."
"A generally great delivery. Effortless. The venturi ± switch actually made a difference. It was spoilt for me by the mouthpiece and the fact that exhaled bubbles rattled my mask and disturbed my view."
"An excellent regulator. I cannot see how the ATX200 can be better. I liked it immensely but it was spoiled by the too-small exhaust-T which caused a lot of bubble interference."
INVERTED: Definitely wet.
SECOND-STAGE ASSEMBLY:As per the Apeks ATX200.
ANSTI RESULT:An initial cracking effort was followed by positive pressure midway through the inhalation part of the cycle. Work of breathing = 0.96 joules/litre.

FIRST IMPRESSIONS: An environmentally sealed, diaphragm-type first stage with an attractive heavy black rubber cover and relatively good hose routeing except that two ports seemed rather too close for comfort. Its second stage has an either-way-up side exhaust and a diaphragm design but the clear plastic of its construction makes it look cheap. A very long- established servo design but its light weight is marred by the heavy swivel-joint on its mp hose. The parts for an annual service are included in the purchase price.
IN THE WATER:
"I can't understand why Oceanic positions this as its best. It was particularly noisy and quite damp. The purge was quite a surprise to use, too!"
"I hated it. It just got wetter and wetter. I had to purge it every few minutes because it seemed so wet, and the purge was very powerful - too powerful for my liking."
"Wetter than an otter's pocket, you need to grow gills to use it - a constantly wet breathe. It seemed better one way up than the other, which is strange for a side-exhaust design. A good route for the exhaust bubbles, though."
"I felt that I was breathing a continuous wet mist which got worse when I looked up. In fact, it was disturbingly wet although it was better one way up than the other, which seemed to make its side-exhaust design pointless. The purge proved very fierce. Exhaled bubbles were routed well away from my face."
INVERTED: Wet.
SECOND-STAGE ASSEMBLY:Front levers off for easy access.
ANSTI RESULT:Assembly: It was easy to disassemble and clean but we feared that some parts could be too easily lost.

FIRST IMPRESSIONS: An environmentally dry-sealed, diaphragm- design first stage with an anodised black finish and excellent hose routeing. Compact and versatile with twin cylinders. The second stage seemed no more compact than former models except for the small exhaust-T. It looked old-fashioned. BRA and venturi ± accessible. The mp hose has a heat-sink included for coldwater use. It comes with standard or Comfobite mouthpieces.
IN THE WATER:
"An excellent breather but instantly free-flows when out of the mouth. That might be a serious issue. It has excellent controls for access even with thick gloves but I would prefer a wider exhaust-T. One of the best."
"A lovely regulator. It tended to free-flow when out of the mouth at depth but the BRA worked so well that I could shut it down if it got out of control. Nice easy breathing. I would buy one."
"A beautiful breathe-in and a hideous breathe-out! Its cracking pressure seemed very low and there was a great volume of air available but the exhaust bubbles gave me a face Jacuzzi, spoiling my view. Streamlining the exhaust-T has minimised vision. Looking up, it seemed quite dry."
"I really liked this one. The breathing was very easy but with a lot of bubbles in front of my mask. Its BRA certainly made a difference. A dry breathe when face-up. Overall, a favourite among lots of good ones."
INVERTED: Definitely wet.
SECOND-STAGE ASSEMBLY:Easily stripped.
ANSTI RESULT: Initial cracking effort followed by positive pressure midway through inhalation. It free-flowed slightly after test, needing the BRA screwed down. Work of breathing = 0.95 joules/litre.

FIRST IMPRESSIONS: A radical design with a heavy first stage which has a unique ball-bearing and large heat-sink spring design. Only one hp and three mp ports. Minimalist features includes a DIN fitting with A-clamp adapter. The ambidextrous second stage is a very compact upstream servo design with a pressure-relief valve on the mp hose. It has a side-exhaust but an offset front diaphragm. No knobs or switches and the test example had an original Poseidon lanyard attached. It required a thumb positioned over the mouthpiece when turning on the air-supply to discourage it from free-flowing.
IN THE WATER:
"It seemed to give an unnatural breathe. You needed to suck to get air, and then you got too much. The purge was horrific! I felt it moved me 3m sideways each time I used it! Impossible to make free-flow but scary when you turned the tank on. It gave plenty of air but pulsed if you inhaled strongly."
"Disappointingly, this seems to be merely a Jetstream in a new set of clothes. You have to suck for your air, then it comes in a rush. When I purged it, it blasted my mouth. If I wanted my tonsils removing I would have gone to hospital! Not for inexperienced divers."
"It felt balanced in the mouth but was like breathing from a machine. The air came in quick pulses and the purge blew out my other end! Exhaust bubbles were routed well away from my face. Very dry face-up."
"Frightening the first time. It gave plenty of air when I wanted it (and sometimes when I didn't) but stuttered in its delivery. The purge nearly blew my balls off! Not for an beginner who needs to share air."
INVERTED:Absolutely dry.
SECOND-STAGE ASSEMBLY:Relatively easily disassembled for cleaning.
ANSTI RESULT:This regulator appeared to have a positive-pressure spike at the start of each inhalation. Inhalation effort was low if uneven. Work of breathing was 1.56 joules/litre.

FIRST IMPRESSIONS: This US company has set out to manufacture its products from materials with "no expense spared". The regulator has a traditional piston-type first stage with a rotating turret and five mp and two hp ports. The second stage is robust-looking, beautifully finished with massive attention to detail. Not at all bulky but with a wide exhaust-T. A very clever internal design does away with the need for a venturi ± switch but it does have a BRA and we thought it had the best mouthpiece of any regulator tested here. We all thought it really cool.
IN THE WATER:
"An excellent breathe and relatively difficult to make free-flow. You could set the BRA and it performed the same at any depth. The exhaust bubbles did not interfere with my vision. The mouthpiece was my favourite. Of all the regulators tested, this is the one I'm going to buy."
"Light in the mouth and absolutely bone dry at all angles. I felt the purge button was a little hard to press but it was otherwise excellent. No problem with exhaust bubbles. A nice regulator. I want one!"
"An excellent breathe. Even beyond 40m it was easy to draw rapid yet deep breaths. Looking up, it was perfectly dry. The purge control was strong enough to empty the second stage but not my mouth and there were no exhaust bubbles in my face. My favourite."
"It felt good to breathe from and the purge was a delight to use. A great design. The controls seemed to make no discernible difference at depth but it refused to free-flow. The mouthpiece was good and solid and the really wide exhaust-T took the bubbles well away from my face. Excellent!"
Inverted: Slightly damp."
INVERTED:Slightly damp.
SECOND-STAGE ASSEMBLY:Assembly: It was easily stripped for cleaning.
ANSTI RESULT:After the initial effort needed to open the valve, very little more was needed during inhalation. Work of breathing = 1.03 joules/litre.

FIRST IMPRESSIONS: The 11th model was the simple regulator that had proved firm favourite in our comparison of inexpensive models retailing for less than £150 (Diver, April 2001). We thought it would be interesting to compare it with the best that money can buy. A simple, unbalanced piston design first stage combined with a nicely finished lightweight second stage.
IN THE WATER:
"The big shock. As good as any of the best, although set up to be on a hair-trigger from free-flowing so that I have doubts about using it in cold fresh water. The breathing was just as good at 40m as at 4m. I wondered at the time how Oceanic decided where this fitted in its product range."
"The best breathe of all the regulators tested here. I can't praise it too highly. Effortless. We gave it applause while sharing it at depth. Face-up it was perfectly dry."
"A very good volume of air at all depths. Generally a good solid supply, though I thought it made a hissing noise. The purge cleared water from the reg without rushing air into my mouth. It was effective but gentle."
"The mouthpiece seemed quite chunky but it gave very good breathing. I liked it but it was always on the edge of free-flowing when out of the mouth. It seemed very natural, though. The purge was nicely designed. After the Omega it was like swapping to fresh air! Great!"
INVERTED:Only slightly damp.
SECOND-STAGE ASSEMBLY: Second-stage Assembly: It proved easy to strip and clean in the field.
ANSTI RESULT: More effort was needed overall than with some of the more expensive regulators but the pressure volume diagram reveals a smooth delivery. Work of breathing = 1.71 joules/litre.