John Bantin has been a full-time professional diving writer and underwater photographer since 1990. He makes around 300 dives each year testing diving equipment.

"How's your boiled egg?" thundered the bishop.
     The new young curate, clearly daunted at the prospect of having breakfast in such exalted company, looked down at the obvious evidence of a developing foetus attached to the yolk, and replied: "Good, in parts."
     So goes the old story. And I, likewise, found the new Sea Quest Raider BC to be "good, in parts". When I was told about it by an enthusiastic purchaser, I got the impression that the Raider was a tidy little wing-style BC that would be ideal for me to pack for a trip on which the all-up weight of my baggage was important.
     In fact it proved to be quite massively built, obviously aimed at the twin-tank user. It weighs in at 5.5kg and the wing is so wide that, when used with a single tank, spinnakers and other large billowing sails come to mind. It measures 73cm across at its widest point.
     I remember, years ago, writing a glowing review of another Sea Quest wing which was quickly followed by a phone-call from a disgruntled purchaser. Having fitted two steel cylinders and fully inflated the buoyancy bag, he had flung his rig over the side of his boat only to see it sink without trace, luckily without himself attached. Not enough lift with that one, then!
     There can be little danger of that happening with the Raider. This wing has around 22kg of lift available, and if that is not enough you have the option to fit a second 22kg redundant bladder along with the twin-tank mounting kit - and a crotch-strap too, to stop the whole lot falling over your head during a duck 'n' dive.
     So what do you get with the basic item? A patented harness that allows full adjustment not only for girth but for height too, a semi-rigid backpack, two cambands for a single tank, and Sea Quest's patent "self-adjusting lumbar support".
     The cummerbund can be customised to fit almost any girth of diver, and this is done with the aid of a cross-head screwdriver. That is not to say that you cannot make instant adjustments by means of the Velcro-covered forward flaps of the cummerbund, or indeed the 5cm webbing with pinch-clip that you wear over it.
     The integrated-weight system is of the commonly used Velcro-flap type but the weight pouches are double-sized, so you could probably fit 8kg of block weights either side of the BC. I wouldn't recommend that, but what you do get is the option to position the weights you use within the pouches accurately, thereby giving you a choice of trim.
     When it comes to using floaty aluminium cylinders, especially noticeable with twins, there is a band that clamps around the tank with two more weight pockets. These will take another 2kg each and are secured with pinch clips. So you could theoretically jump in with a single cylinder and 20kg of lead. Sea Quest claims 19kg, which should keep you down all right!
     The more water you displace (that's body volume, not weight), the more weights you need. In a drysuit and bulky undersuit even I, at 1.95m tall, normally use only 14kg with a 15 litre steel tank. I can't foresee anyone needing to use much more unless you're using twin aluminium tanks, in which case I can see business looming for a physiotherapist.
     If you do need more, you're probably doing it wrong, so I hope no-one is silly enough to load this integrated-weight system to the maximum, which takes us back to the unfortunate diver I mentioned earlier.
     There are two cambands for a single tank, four for twins. Like most, if not all Sea Quest BCs, this one has the swivelling buckles to each shoulder strap which help with fit. There are also six pre-bent stainless-steel D-rings, two of them adjustable for height, for clipping on the ancillaries.
     Two shoulder dumps, the right-hand one threaded through the front shoulder facing to a large toggle, make dumping air when dropping feet-first easy. There are two bottom dumps, designed to aid a head-first descent and for draining water from the inverted-U-shaped bladder.
     Two large zipped pockets are mounted either side of the harness and these are big enough to stow a small reel and DSMB. Finally, the whole thing can be lifted by means of a handle with a thick rubber covering to stop it biting into your fingers - and you need it. I made sure to carry my rig on my back when out of the water. The patented lumbar-support helps keep things comfortable.
     So why was it only "good, in parts"? Well, the two cambands and trim weightbelt made it complicated when it came to swapping tanks but, more importantly, with a 15 litre steel cylinder and a drysuit, I found that, however I installed the weights, I was tipped dangerously head-down under water.
     This effect was so powerful that I spent each of the first three dives on which I tried this combination finning desperately to prevent myself becoming inverted. It certainly spoiled my fun.
     The Sea Quest Raider is made in Mexico, and steel cylinders are unusual on that side of the Atlantic. I suggest that this BC is designed for use with twin aluminium cylinders when using a drysuit, though you will then need to use a great deal of lead. When I swapped to a wetsuit I needed fewer weights. I still needed 2kg more than normal just to overcome the inherent buoyancy in the BC, but at least I could relax.
     Getting air out of the BC proved something of a challenge too, because so many creases are formed in which odd bubbles can lodge. I needed to pull both bottom dumps during a head-down descent and had to be very careful during head-up ascents. I could hear water trickling about inside as I did my best to shed the last remnants of air.
The Sea Quest Raider in basic single-tank form costs £500.

A band clamps around one or more tanks carrying two more weight pockets that will each take 2kg weights.


Adjustable straps are designed to stop the wing billowing, though even on the tightest setting they were not entirely successful

Split fins face the ocean test
After the results of Diver's fin comparison test last month (Split Decision, September), I was gagging to try a pair of the winning Apollo Biofin Pros out in the open ocean.
     I had been sent them in sizes M, L and XL, but I had a problem. In the wetsuit boots I was using, my feet were still too big to fit any of them. Well, you know what they say about men with big feet. We need big boots.
     The problem seemed to be not in the width of the foot-pocket but in the height. Thick soles and reinforced uppers on wetsuit boots just blew my chances of getting my feet fully inside them. I had to search around for a less chunky pair of boots before I went anywhere with them, which begs the question, will they fit your drysuit boots? It makes sense to try before you buy.
     The Apollo Biofin Pros are made entirely from natural rubber. I had begun to forget what that smelled like. It's not very pleasant and some people will find that they are allergic.
     Japanese Apollo was the first manufacturer to adopt the Nature's Wing split-fin design and these are the latest version. I got them from Apollo USA.
     We have grown accustomed to thermoplastic fins, but while rubber is much heavier I can vouch for its toughness and longevity. My original black rubber SeaMaster fins lasted 30 years and were still in perfect condition when I tried to give them away at a car-boot sale.
     No-one was interested then, so they went into a skip with other unwanted clutter before I set off for home. If only I knew then what I know now. They started to be considered the latest thing in Japanese dive shops about five years later!
     The all-rubber Biofin Pros are available not only in black but in a rather attractive metallic blue. They have standard quick-release buckles and heavy side struts which keep them rigid along their length.
     I was full of enthusiasm for the first fins I tried. These gripped my foot in the foot-pocket right up to the heel and made me feel as if they were part of me, taking all the strain off my ankles.
     I was disappointed to find that the Biofin Pro has abandoned this design idea and that my heels protruded. It was inevitable that this would prove a bad idea and I noticed after some time in the water that my legs ached in places where they hadn't ached for a long while. "Get used to it," I hear you say.
     The Biofin Pros propelled me along all right, though I was inclined to turn round to see who was behind me until I deduced that the sound was the effect of the two parts of the fin blades coming together and knocking from time to time.
     Their unusual weight helped keep my feet at a good angle relative to my body, so no ankle-weights would be needed, even with a drysuit.
     I admit to having been scathing about some other split-fin designs which I have found disappointing, especially in an oncoming current. These split-fins were not disappointing - they work. In fact, they're excellent.
Apollo Biofin Pros cost around US $200 (£130) a pair.

A touch of Scottish glamour
BMWs are defined by their model series number and engine size. I can make sense of a 520i - it's the series 5 saloon with a 2.0 litre injected engine. But I get confused by the model designations of Gates drysuits. Why couldn't it give them names?
     Gates model numbers seem completely arbitrary. And why does the manufacturer persevere with the idea of adding the word "Pro" to all its suit designations? The new Pro SBX 400 is squarely aimed at leisure-divers.
     It looks very much like the Pro CBX 450 already reviewed in these pages, and it has all the features I liked about that suit, including a latex neck seal and long conical latex wrist seals that really do keep the water out, whatever I do under water.
     However, while the CBX offers a more flexible version of the almost bullet-proof Pro VSN 1100, one of my favourite suits of all time, this new SBX suit comes in a more lightweight polyester material for those who don't want to lash out quite so much cash, and for whom light weight is more important than total longevity.
     That said, don't confuse this with some other drysuits available that seem to be made from the weight of material normally reserved for plastic macs. This stuff looks tough.
     I was invited to dive around a small Italian island in mid-June. Images of lazy summer days and water lying limpidly blue were tempered for me by the knowledge that the Med has not begun to warm up so early in the year, and that at depths of more than a mere 15m it could be chilly enough to freeze the balls off a brass monkey.
     So I welcomed the timely arrival of this suit just as I was packing to go. European baggage allowances meant that its overall light weight would be helpful, and I was happy to use any suit so long as it was able to keep my warm undersuit dry.
     The use of a polyester material has given Gates the opportunity to print a design pattern on parts of the suit, thereby making it prettier. Now the idea of a stylish drysuit is an odd one. I'd go as far as to say it was an oxymoron. Certainly Dumfries is not well known in the glossy world of Vogue or Harpers as a centre of style, but if French fashion designer Jean-Paul Gaultier can wear a kilt, why not let the Scots have a go at putting a bit of pizzazz into what must be the most unglamorous of sportswear?
     Anyway, surrounded by Italian divers in their colourful wetsuits, I felt less than dowdy. The blue watery pattern of my Gates suit co-ordinated nicely with the colour of their noses once we surfaced after a long dive.
     I stayed nice and dry thanks to those long wrist seals. Wrists are always a problem for me because I need to hold my camera up to my eye. This causes air to migrate to the wrists, and the resulting sinewy arms can break the adhesion of a more modest seal.
     My feet stayed warm and dry too, in the neoprene-lined boots provided. Gates should know about boots, because it makes the famous Hunter wellies so beloved of royalty and others equipped with a Range Rover and two golden retrievers.
     However, the royal shooting party never finds itself under water trying to maintain an equilibrium. The boots proved very buoyant, so I believe most users will find themselves using ankle weights to keep their legs down. I certainly needed them.
     Another small criticism I found was that, in competition with my sleekly wetsuit-dressed Italian buddies, I was very much less than aquadynamic. They were darting about all over the place, whereas it was all I could do to trudge along behind. That probably goes for all membrane drysuits.
     As on all other Gates suits, the seams are vulcanised on the inside, using the same ovens as for the Hunters. Goodness knows how they do it without melting the whole thing. Anyway, leaks at the seams should never be a problem. Internal braces help with dressing and there is a heavy-duty cross-shoulder zip.
     Finally, a rotating inlet valve on the centre of the chest and a constant volume auto dump at the upper arm, both bearing the Gates name but looking very familiar to anyone from Blackburn, Lancashire, completes the deal.
     Gates suits can be bought through most dive shops, but can also be bought direct from Innovation Drysuit Supplies, a company associated with Gates.
The Pro SBX 400 costs £435, or £410 in all-black.

Nothing dumb about this baby
"Dumbing-down" was a concept invented in America. That's not surprising. It's what's needed when you have a vast population drawn from disparate cultures and speaking different languages, homogenised into one incredibly prosperous industrialised society.
     Simply constructed cars, fast food and pared-down education have each been spawned from such a philosophy, and no-one can deny that General Motors, McDonalds and PADI have each been very successful in their own fields.
     But not all Americans drive gas-guzzlers and eat only bap-bound burgers, just as not every American diver sticks to no-stop dives at less than 20m.
     With such a huge population, the USA must have more divers who like to go deeper into their chosen activity than Britain's entire diving population.
     The term "technical diving" was also coined in America, mainly to distinguish those who dive like Europeans from the majority who certainly do not. Dive Rite, headed by Lamar Hires, a technical trail-blazer, has aimed to supply the demand for diving equipment that goes beyond the Recreational Dive Planner and the lurid Lycra suit.
     It came as no surprise to find Dive Rite supplying proper decompression computers back when most US divers thought that using a diving computer meant concentrating on keeping its display-graphic from entering the red sector.
     The most high-profile of these computers, this side of the Atlantic, has been the Nitek3. This was the first, and until recently the only, readily available computer that could keep track of a diver's decompression status even if he changed to one of two alternative and richer mixes of nitrox for accelerated decompression during an ascent. But in all the excitement, the basic Nitek seems to have been overlooked.
     I meet many US divers who are both certified to use nitrox and happy to dive deep enough and long enough to require mandatory decompression stops. Many of them come equipped with this admirable bit of kit.
     With a display almost identical to the Nitek3 and a similar pair of push-buttons, the Nitek is considerably smaller and with a characteristically similar rectangular case with a stretchy nylon strap that should go round the fattest drysuit wrist.
     It can be adjusted for nitrox mixes between 21% and 50% and has a predetermined maximum ppO2 alarm set at 1.6 bar.
     There are no short-cuts with the manual. Far from dumbed-down, it is designed to be read from cover to cover. Don't hope to dip in midway and find out how to make the nitrox setting.
     First you must set the date and time, and whether you want imperial or metric readings. If it is not set for air, you must be sure to set your nitrox mix immediately before every dive.
     During the dive the computer gives the full range of information you need, including stop-depth, stop-time and total minimum safe ascent time once you have gone past the last of your remaining no-stop time.
     The build-up of absorbed nitrogen prior to that moment is represented by a bar graph of rectangles that gradually builds up, and in nitrox mode that is balanced by the oxygen-limit warning, with a similar bar graph of round blobs that build up on the other side of the screen.
     If at any time the figures in the display start pulsing, it means that you are doing something wrong. This is accompanied by both an explanatory icon and an audible alarm. You might be ascending too fast, or be too close to the ppO2 limit for the mix of nitrox you're using.
     If both the oxygen limit and the ppO2 limit sound early on in a dive, it probably means that you forgot to set your nitrox mix, and the Nitek has defaulted to a worst case theoretical 79% nitrogen, 99% oxygen setting. As this will happen at only 6m, you have time to get back to the surface and reset the mix adjustment. Alternate displays for ppO2, water temperature, and "how long till lunch?" are accessed by pressing button A during the dive.
     It was a shame that the display had no independent illumination. This rather precludes it from use during night dives, or indeed dives around the coast of Britain where poor visibility might reduce you to peering at it with your torch.
     What proved most significant about the Nitek is that it appears to me to use the Buhlmann ZH-L16 algorithm, probably one of the most field-tested algorithms used in any diving computer today. Its siblings have always done well in Diver side-by-side comparisons and I had lots of confidence in the information displayed.
     It also seemed to want me to stop in the 5-3m zone for a few minutes extra after any deco-stop dive, although there is no displayed "safety-stop" as such.
The Dive Rite Nitek is PC-compatible and costs £296.