First post in a long time (forgot my old id/password and it was tied to an expired email account).
Here are my two cents on backplate/wing versus "normal" bcd.
A normal BCD will give a new user a feeling of greater security if they are bobbing on the surface after a boat dive. You can inflate the thing so that it holds you completely upright and gives you a comfortable "hug".
A BP/W on the other hand will push you onto your face if you are in an upright position on the surface and decide to inflate the thing to the max. On the other hand, if you deflate and lean back and re-inflate, its a lot like laying on a raft in the pool.
The real advantage of a BP/W is found underwater. All your bouyancy is in a single plane - on your back, instead of some air being on your side. Thus you tend to stay in a more horizontal position relative to a "normal" BCD. Another great advantage is the fact that you take weight off your hips. Instead you have most of your weight (if using a steel backplate) distributed evenly along your back. This enhances your stability underwater.
If you want to feel comfortable wearing something to control buoyancy while standing in the local dive shop or sitting on the surface, the BCD is the way to go. If you want increased comfort and control underwater, I would go with a BP/W.
I've known a lot of divers who have gone from a BCD to a BP/W, but not too many who have gone the other way.
