STAs and What size wing for BP?

[fishchaser]

Two questions, splitting this off of the BC thread:

What size wing would be recommended for a single tank? The Dive Rite Venture is 30lbs, but no possible doubles. The Trek is 40, and double capable. And the Rec is 51#. I'm not sure I will ever dive doubles, and not sure if the 30 pony counts as a small double or not. Doesn't seem like any ($20) price difference between the 3. Is there an obvious size (profile) difference to the three?

I read on :

If you occassionally switch between doubles and singles, you can configure your backplate to attach to a single tank by adding two tank straps threaded through the tank strap slots of the aluminum and stainless steel backplates.

Does everyone agree with this? No Single Tank Adapter necessary? It looks like the tank would be less stable, or not?

Chad