Hypothetical: Buying without diving it first

[fjpatrum]

Put on a thick wetsuit and fully inflate the BC while wearing it over the wetsuit. Make sure there isn't significant squeeze around the torso. Inflate it partially and see if someone can pull it up using the shoulder straps (IE will it ride up on you in the water).
These are the biggest reasons I moved to a BP/W.

Other considerations:
Complicated weight pockets suck. Can you insert and remove weight pockets with the BC inflated and weights in the pockets? Soft weights too? Are the pockets secured by Velcro or some other method? (Velcro wears out, which can make the pockets slip out easily when in horizontal trim. Conversely, new Velcro makes the pockets more difficult to insert under water, especially with air in the BC.)

For "storage" pockets, can you actually put anything in them with the BC inflated? I had "huge" pockets on my Genesis Phantom BC but couldn't use them easily if there was any air or weights in the BC.

These are honestly the only things I would worry about. For the most part a BC is a BC if it will stay on your body.

 

[fjpatrum]

Why would an OW student be buying gears before knowing that he or she would pass the course? That's like putting the cart before the horse.

As far as how to determine which BC to buy nowadays, it's pretty simple FOR ME. I can't dictate how others will do it, but for me it has to be a BPW. Then it will have to be either Dive Rite or Halcyon. Though I don't think that I'll be buying any more BCs soon. Three BCs are more than one man would need.

Plenty of people buy gear before the "know they're going to pass the course" because for 90% of people taking OW it's trivially easy to pass. Yes, I pulled that statistic out of my keaster, but let's be honest-how many people actually fail OW class? Now, whether or not it's a good idea to buy gear before you know what to look for is another subject entirely.

 

[a22shady]

Definetly trying everything out 1st is an advantage however just becuase you dont try something doesn't mean you wont like it either. For me I did all the research I could and bought everything without trying except my regs and very happy so far 2yrs. The one thing's I tried were my reg's I actually thought I wanted Oceanic CDX5 I think that the model untill I paid to get into the pool and try out a bunch of different reg's good thing too cause I didnt actually like that reg. I bought ScubaPro MK17/G250V. Again after that just based off review I bought the Atomic M1's and very happy with them.

For my BC I actually never tried it on. We were shopping for my G/F as finding a BC for her was difficult as we couldnt find anything she liked or fit very well. SO we went from shop to shop untill one sales lady had said well I dive the Halcyon Eclipse system. We have seen thins in the shop we trainewd with but passed on it. But this time she say's ok Ill try it on next thing she loves it. I already checked it out ahead of time but never tried it on. So I told the lady we will take 2. Never tried on in store or in pool. Still dive with it today and very happy.

So if your biuying a traditional Jacket BC I would say trying it on and out would be alot more important. If you are going to go with a Backplate/Wing trying it still would be nice but I would say not as important only because these are customized and fitted to you. so it will fit right.