BC snug fit or lift capacity, which is more important?

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That was my thought, if either fit or lift is actually a problem with a BC you're looking at, you should look at a different one.

As far as going by the size charts, I take it she hasn't had the opportunity to try either on yet. She's just not going to know until she does.

Are you comparing 2 sizes of the same BC, or 2 different BCs? If the same, what BC has trim pockets in one size and not another?
 
Thanks very much everyone for your responses, they were very helpful. To answer some of the questions: we want to buy her a Seaquest Pearl, which comes as a part of a full package, at an attractive price, so our choice is a little bit constrained in this regard. It was very hard to find a place that would carry sizes S and XS and where she could try it on to compare the fit. She will dive mostly in warm waters, in the ocean, wearing a 3-5mm wetsuit.
 
I wouldn't buy a BCD without first doing an in-water dive demo with it.

Many dive shops will rent out gear similar to the items they sell. This is a great way to test out how easy it is to exhaust air from the BC, whether the trim weight pockets are in the right location, and how secure the tank is held by the tank camband straps. It's also nice to be able to verify that the BC has enough lift for the gear configuration (wetsuit, tank) you're using.

Joining one or more local dive clubs will expand your circle of dive friends. Not only will this give you more opportunities to dive, but often times friends will allow you to try out their gear for a dive or two. Once again, the ability to do an in-water dive demo is invaluable. Trying on a BC in a dive store can be misleading in terms of how well the BC might perform in a horizontal position in the water under "real world" conditions.

One thing that I didn't appreciate prior to trying out a friend's BC was how useful a crotchstrap can be. It really helps anchor the tank flat against your back. The BC just feels "solid" when using a crotchstrap; the jacket doesn't ride up by your ears when it's inflated on the surface. The obvious disadvantage is that ditching and donning the BC is complicated by the presence of the crotchstrap, but I feel like this minor inconvenience is worth it.

One of the common things that many BC manufacturers are offering nowadays is a combo octo/power inflater. There are pros and cons to this approach to an alternate air source. The most important thing to do if you have this octo/power inflater setup is to practice shared air ascents with it...frequently. Vacation divers typically aren't "fluent" with the operation of such devices. This is clearly a safety issue.

Another recent trend in BCs is an up/down lever instead of a conventional power inflater with separate inflation and exhaust buttons. The "levers" are being marketed very aggressively by certain manufacturers. When evaluating modern dive gear design, understand that "newer" does not always mean "better." A diver's buddy needs to be able to operate the gear in the event of an emergency (unconscious, panicked, unresponsive diver). In terms of maintenance, the levers haven't been around long enough to investigate whether they break easily or they cost a great deal to repair. On the other hand, simple power inflaters can easily be overhauled in the field in minutes, and, if they can't be repaired, they are easy to replace with a couple of zipties. A spare can be kept in one's save-a-dive kit.

Hope this helps...
 
You seem to be equating required lift with the size/weight of the diver, and maybe that's where you're mistaken. Lift is needed ONLY for two things; 1) to compensate for wetsuit compression and gas weight, and 2) to float the rig without the diver in it. Since it's safe to assume that a properly weighted recreational diver will not be negative at the surface apart from his/her rig, if the BC can float the rig itself, it can also float the diver in the rig.

Unless your wife has a wetsuit that will lose 18lbs of buoyancy and she's carrying more than 5 lbs of gas, I can't imagine a scenario in which she would need more than 23 lbs of buoyancy.

Fit is everything in a BC, that's one of the reasons I hate jacket BCs so much; I've never seen one fit well in the water. My experience is that they're restrictive around the chest/diaphragm, they ride up your torso on the surface, and they're sloppy with holding the tank in place. You said that a BP/W is "too hardcore" but I think that's a misguided statement. Why don't you let her try a couple of options, including a rigid plate with webbing harness, in the pool before making the decision for her?
 
Thanks very much everyone for your responses, they were very helpful. To answer some of the questions: we want to buy her a Seaquest Pearl, which comes as a part of a full package, at an attractive price, so our choice is a little bit constrained in this regard. It was very hard to find a place that would carry sizes S and XS and where she could try it on to compare the fit. She will dive mostly in warm waters, in the ocean, wearing a 3-5mm wetsuit.

unclear - you want to buy her a Seaquest Pearl because she likes it and it has the proper fit, or because it's part of a package? If simply because it's part of a package, that's a problem with packages - you get nudged into buying something you may really want or be right which is usually a false economy. Many shops (internet and otherwise) will work with you to put together a "package" price on what you really want. They're not generally wed to their pre-designed packages, but offer them because for various reasons they will sell to some people.

If that's the BC she really wants, then it sounds like either has enough lift - I think it's hard to buy a BC that doesn't have enough lift for warm water diving. So she should buy whichever fits best, period Given the hybrid style, a lack of trim weight pockets may not matter to her. If it does, there are other solutions like a pocket on the camband.
 
I will say from personal experience as a small woman, that having a BC that shifts and won't hold the tank stable is a major PITA. We have taken to outfitting our students in BCs one size smaller than what they appear to need -- it's made their lives much easier.

That particular BC is not one I would buy, and runs at the high end of the price range.
 
Here is a calculator which should convince you that 23 lbs is plenty: http://www.scubaboard.com/forums/bu...ems/158370-ultimate-wing-lift-calculator.html
I have also read on SB the formula for determining wing lift is exposure suit compression + gas used = lift required. A 5mm suit should have a buoyancy of less than 10% of body weight so for your wife, 10 lbs, plus 4 lbs of air breathed on a AL80 = 14 lbs minimum. Better to add a few extra pounds to be conservative.
 
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That particular BC is not one I would buy, and runs at the high end of the price range.

What is it about the Pearl that you do not like? Curious since I went shopping with my wife and she actually liked that the best out of the 3 or so she tried on. Granted she's been using a jacket style for a billion years and not interested in changing (no i3 for her either :) )
 

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