Ben
You're going to get alot of different opinions on this and none are wrong. Its a preference thing and what works for some may not work for others. As always, try to get out and try as many as you can BEFORE buying or you may be stuck with something you hate. Our team chose a certain BC because a bigger team in the area was using them so they must be good right? Thats the biggest mistake our team could've made.
Different opinions here too but a properly weighted diver doesn't need a whole lot of lift unless you're using neoprene exposure protection (which you shouldn't be). A human body in water weighs 8-16 lbs negative. If a tech diver can dive double steels with 3-4 stage bottles, scooters and who knows what else with a wing of only 55# I'd say 65# of lift is total overkill for a PSD with a single and pony. I'd say 45# is probably the most you'll ever need
I like back inflate because it trims out nicer and makes movement underwater easier. The argument that a back inflate will tip you forward on the surface is true only if the bladder is fully inflated (which you rarely need to do). We spend most of the dive underwater not on the surface so I'd like to focus on the underwater characteristics more.
Our team ended up with the zeagle 911. These are by far the worst BC that I've ever seen (except for maybe the HUB). The 911 is the same as the SAR except it doesn't have the harness integrated into it. The standards we must follow won't allow an integrated harness anyway. Look at this post to see how I really feel
http://www.scubaboard.com/t66415-.html
I did try an XL of this BC but probably should have had an L. It was comfortable and functional. I'm not a big fan of pockets on a BC but these ones are probably the best if you're into pockets. The pony bottle pocket is a great feature. Overall I'd say it was above average and thats coming from a back inflate fan.
What I would suggest is something simple and tough like a wing with a back plate and harness with quick release buckles. The black diamond is a close second but I'm starting to move away from anything with integrated weights as well.