GrumpyOldGuy
Contributor
For your budget the best back inflate BC IMO is without a doubt the Zeagle Express Tech. You can find them for around 250 new and by adding a crotch strap (I make my own for about $7) 4 d rings and sliders and a metal buckle from Piranha Dive Gear, you come in under 300 for a BC that is infinitely adjustable, rugged, has no inherent buoyancy, and can actually be modified easily for side mount or small doubles. Wings are interchangeable and range from 23 to 35 lbs of lift. Integrated weight systems are available for it but IMO not necessary. I use a belt with mine in addition to an XS scuba weight pouch on each cam band. Using these trims it out just like my plate and wing. I did a review of it a while back with pics of my set up. I have gone to the 35lb wing on mine since I dive steel tanks.
Just an FYI - back inflates do not push you forward on the surface. What pushes divers forward is improper weighting coupled with over inflation of the BC. All that needs to be out of the water is your chin. Some people seem to like floating chest high. If you need to have more out of the water with a back inflate you just lean back and relax. Just like being on a pool raft.
The review is here: Zeagle Express Tech Buoyancy Compensator Review
I just put together exactly what you recommended. It's my 4th back inflate over the last 30 years (not to mention an ill-fated jacket that just won't die), clearly the best and most cost effective solution of the bunch. Not only well made and durable, it packs up very small for travel.