First impressions: A high-quality-looking piston-type first stage with four mp ports and a tapered barrel to aid hose layout. The soft cover of the second stage is easily removed and replaced for cleaning and the well-made diaphragm fits snugly, although the demand lever looked modestly made. There was no hose protector to the second stage.
Under water:
"Slightly tighter than some of the other good ones. No problems. An easy breathe. I did not like the mouthpiece (Comfobite). Good, but not as good as some others."
"A good delivery of air which I could not fault. The venturi ± switch seemed to make no difference at depth. I didn't like the mouthpiece. It was much better with the conventional mouthpiece. It had one of the worst purge controls."
"It was comfortable and the air seemed to come pretty easily. Head-down it was OK too. The purge was hard to operate. I liked the Comfobite mouthpiece - it proved very secure in the mouth. Overall, a good one."
"Good. Very easy and smooth but not the best. Quite dry. The purge felt stiff."

Inverted: Very wet.
What the machine said: Not a particularly even breathe, with some positive pressure at the end of the inhalation cycle at 51m. Work of breathing 1.88J/litre (limit=3.0 J/litre). An acceptable performance; this regulator met EN250: 2000 criteria.

First impressions: The balanced diaphragm environmentally sealed first stage looked to have a poor-quality casting but the four mp and two hp ports were well-positioned. We felt that the second stage looked nasty and brittle, and the breathing-resistance adjustment knob needed nine turns to complete its range. However, its front cover was easily removed and we were surprised to see that it had a rather nice roller-bearing to its demand lever, and two exhaust valves.
Under water:
"It varied from really tight to almost free-flowing as the breathing-resistance knob was adjusted. The air could be made to be delivered with such a force it stung my tongue. The second stage is just too big. Not the valve I would choose."
"Not as bad as appearances would have led me to expect. There was some effort at times. It was comfortable but felt and looked cheap and nasty, which did not inspire confidence."
"Definitely not my favourite. It was too big, wet when face-down and there was either too much resistance or it was set for heavy breathing. It will free-flow at depth when the knob is opened up."
"I was surprised that I liked it so much once I got used to its cheap plastic looks. It really needs personal tuning with the knob provided. It gave a real blast once it was opened up."

Inverted: Almost dry.
What the machine said: This regulator failed to meet EN250: 2000 criteria at depths past 33.2m, as the diagram shows.

First impressions: A good-looking item that seems well-engineered. The piston-type first stage has four mp ports and a chunky rubber-covered knob to its A-clamp. The second stage is easy to open for cleaning. This cover has a steel locking pin. The demand lever is coated.
Under water:
"Air was received easily on demand. I thought it was OK until we started to tandem-breathe at depth, when it began to flutter noisily. Otherwise it was very good - a faultless performer."
"No problems head-down. It felt nice in the mouth and there was no effort to breathing. Very good. The mouthpiece was just right. It shines out among some of the others."
"I liked this one a lot. It was very easy to breathe - soft. It was dry in all positions except when inverted. Very comfortable. One of my favourites. I could have confused it with the one that ultimately was proved the best."
"A good flow of air. It breathed well. It juddered and fluttered with two of us on it at depth, otherwise it was soothingly quiet."

Inverted: Slightly wet.
What the machine said: A very reasonable result at 51m. Work of breathing was 1.88 J/litre (limit=3.0 J/litre). Very good.

First impressions: The impressive-looking diaphragm-style first stage is environmentally sealed. It has four mp and two hp ports arranged around a vertical barrel for easy hose routeing. The second stage was easy to disassemble and reassemble at the beach and the hose comes from it at a convenient angle. We were sent a DIN-fitting first stage and only one second stage, which made it impossible to test for tandem breathing.
Under water:
"This really did require some effort to get a full lung of air. NFG!"
"Lots of effort but not impossible to breathe. There's an effort to breathing off it, no doubt about it. A bit difficult at times. It looks cheap. Lightweight in the mouth."
"Harder to breathe from than most of the others. There was lots of resistance and there were background noises too. When I went face-down, it was always wet. The mouthpiece is a bit too deep for me."
"Appalling. A slow drag and a real effort to get any air at depth. Very unpleasant. Inverted it felt no worse because it could not get worse!"

Inverted: Dry once purged thoroughly. Otherwise all water and no air.
What the machine said: This regulator failed to meet EN250: 2000 criteria at depths past 33.7m.

First impressions: The impressive-looking diaphragm-style first stage is environmentally sealed. It has four mp and two hp ports arranged This unit exudes high quality. It has a wide A-clamp with a high-quality, rubber-covered knob. There are five mp ports, although one is a wide-bore (DFC) port for the primary second stage, which limits hose layout. It looks well-engineered. The hose has nice hose protectors at both ends.
Under water:
"Plenty of air - almost too much. It was a bit whooshy! Out of the mouth it had a tendency to free-flow. Inhale really hard at depth and you can get a little water. Otherwise a nice breathe, and it performed almost without fault."

"Noticeably more air than others. Head-down it was even better, if anything. One of the ones I would buy. A very good valve. Excellent. An easy breathe. Nice, nice, nice."
"Very light effort - maybe too light. It made my teeth cold. It feels near to positive pressure. I got the impression it was giving more air than I needed. Easy breathing, though it felt too mechanical and not natural."
"A real rush of air. A bit of a blast that was cold on my teeth. Some noise on inhalation. It was not smooth but it was steady. A powerful, solid flow."

Inverted: Moist but manageable.
What the machine said: A positive pressure to the inhalation cycle at 51m of over 5mbar (inhalation line into the red) resulted in failure to meet the EN250: 2000 criteria.

First impressions: Only three mp ports means that this valve is unsuitable for drysuit divers. It looks cheap. The second stage has an unusual teardrop shape that did not appeal to any of the testers at first. We were unable to remove the front cover.
Under water:
"I liked this demand valve. It gave a nice, smooth, easy delivery, although it had a 'plastic' sound. I particularly liked the purge control because your index finger is naturally drawn to it. Its performance under water was faultless."
"OK. No effort. An easy breathe. A big second stage but not bad in the mouth."
"Comfortable breathe but the mouthpiece was too wide for me. Not too bad. A very hard mouthpiece. You get used to it. A good air supply but it sounds 'plastic'. I wouldn't mind doing any dive with it."
"Very pleasant, good, steady, smooth. A good strong delivery of air with little resistance. A very light breathe or the air came in torrents when you wanted it. I could just about manage when it was inverted. I liked this one very much."

Inverted: Lots of water.
What the machine said: Nice, even breathe but with slight flutter (see jagged inhalation line). Work of breathing was 2.32J/litre at 50.8m (limit=3.0J/litre) and the regulator met EN250: 2000 criteria.

First impressions: There are four mp ports and nice hose protectors on the piston-type first stage. The second stage is attractive, easy to reassemble after cleaning and has a very nice demand-lever mechanism with a roller bearing. It is not over-designed. Very neat.
Under water:
"A nice, easy breathe. It delivered air smoothly, without the sudden rush. Very soft and smooth. You hardly notice you're breathing. Silky, velvet-like, silent. I appreciated the compact and light second stage. Excellent. A pure delight. Probably the best regulator tested."
"Excellent. No effort. It was light in the mouth. Head-down it was OK too. Streets ahead of the others."
"OK. Good. Comfortable. Pleasant. You can easily forget you're breathing through a valve. Every time I used it, my thoughts were confirmed. Among some other good valves, this was the best."
"Outstandingly smooth. Others seemed far less smooth when I switched from this one. The most natural breathe, with an exact response to demand. A treat to breathe from. It seems a cut above the rest."

Inverted: Almost dry.
What the machine said: An almost perfect result, as the profile reflects. Work of breathing at 51m was 1.68J/litre (limit=3.0 J/litre). Remarkable!

First impressions: A good old diving-school favourite, the first stage has a protective cage and the hose has protectors with locking nuts. The second stage looked big and bulky by modern standards but it proved easy to take apart at the beach for cleaning out any sand that got in. It has a venturi ± switch. Under water:
"It seems dated in comparison to the others. A good, steady breathe. The venturi ± had no effect at depth. Nice, but not in the same league as the best."
"Good, but heavy in the mouth. I liked it. It's my kind of regulator, although it was inclined to be noisy."
"Some resistance to inhalation but not a problem. Some cracking pressure needed. A little stiff. It feels bulky. A nice breathe but noisy with it. I never realised how big it was before I compared it with these others."
"Not as good as some of the best but a good solid breathe. Not much effort but more resistance than I like. A little stiff, a little mechanical and a little too big, but no problems at 43m with two of us breathing from it."

Inverted: Damp but useable.
What the machine said: Some work (2.15J/litre) required to breathe at 51m (limit=3.0J/litre) and slightly uneven when valve first cracked open at the start of each inhalation (see spike on diagram). This regulator met EN250: 2000 criteria.

First impressions: Four mp ports and good hose protectors. We were unable to take the front off the second stage to look inside it. It has a large A-clamp and knob. This one started to look scruffy before the week's testing was finished.
Under water:
"Quite hard to suck on at all depths. It had a noticeably higher cracking pressure than others. It required a lot more pull. It appeared to need more effort in the shallows. The air was OK but I didn't like this one very much."
"Not as good as some others. There was a certain amount of resistance to heavy inhalations."
"A lot harder to breathe than the others that day. When not head-up, it gives water. Not for a beginner. It sounded mechanical, which did not inspire confidence. It made you very aware of your breathing."
"Noticeably hard work. Quite noisy. It felt very mechanical, quite strained. I switched as soon as I could to another regulator and enjoyed the benefit of doing that!"

Inverted: Often a good delivery but no air at all on one attempt.
What the machine said: This regulator met ANSTI criteria at 50.5m but the work of breathing (2.42J/litre) was higher than some other regulators tested here (limit=3.0J/litre).

First impressions: Only three mp ports means that this regulator is unsuitable for use by drysuit divers. It was reasonable-looking but there were no hose protectors. The lightweight second stage seemed identical to that of the Effesub tested alongside it.
Under water:
"A tight breathe. After too-deep inhalations it made me cough because of spray. Makes you shallow-breathe because it is so stiff. Not at all comfortable."
"Not a particularly good delivery of air and not that comfortable in the mouth. It tended to be wet. I would not consider buying this regulator. It is just too heavy to pull on. I preferred not to use it."
"I would not buy this one. You really have to suck to get air. It ached in my mouth. You really have to suck like hell. Inverted, it was all water. Not my favourite."
"Really bad. I felt it gave a lot of water. There was certainly not enough air for two in a real emergency. Three shared breaths was all I could stand at 40m plus."

Inverted: Very wet.
What the machine said: The initial part of inhalation at 51.2m required more effort than the latter part (line drops sharply into blue area). Total work of breathing 2.10J/litre (limit= 3.0J/ litre). This regulator met EN250: 2000 criteria.

First impressions: The highly chromed piston-type first stage of this regulator looks a bit old-fashioned. It has the same dry-bleed system as other Sherwood regulators. There are four mp ports and a good hose protector. The second stage is oval-shaped, very light and compact but with a wide exhaust T like an old-fashioned moustache. The soft front peeled off easily to reveal unimpressive internals.
Under water:
"On descent it made loud rasping noises. At depth this noise disappeared. It needs extra effort to get a maximum inhalation. A hard delivery of air and an uncomfortable mouthpiece. The purge was not conspicuous but it worked almost by pushing anywhere on the front."
"Well-named! I was unimpressed. There was some resistance to inhalations. A new diver with this one might think that diving was harder than it is. It wasn't nice in the mouth either."
"The air supply was OK but it was very hard breathing. I found it uncomfortable in my mouth because the mouthpiece was so deep and bulky. I would not recommend this one for beginners. It was too damp."
"At first I thought it gave a good delivery of air. I couldn't really fault it. Quite good. Then at depth it became wheezy. A bit rough. Surprisingly, it almost seemed better with two of us tandem-breathing! "

Inverted: Very wet.
What the machine said: Regulator required more work of breathing than some others at 50.8m at 2.38J/litre (limit=3.0J/ litre) and the pressure/ volume diagram revealed some unevenness of supply. Nevertheless it met EN250: 2000 criteria.