scubajoh44:
I agree. I didn't think it would be THAT much better. I just needed a new "BC." I will never go back to a vest.
I'm not sure what you were diving. I dive a back inflate zeagle, so does Kent, and a lot of people for that matter.
If you are set on a BP/W, then plan on spending between $400-600. There are some listed on Ebay, but the truth is that while BP/W's are popular on SB they are not that popular with most divers. They are not nearly as easy to find used.
In addition BP/W divers customize their needs around the diving they do so by default many of these kits come in pieces, and you need to understand what you want before you buy, so you don't make a mistake as I assume you did with this last 75# monster of a wing purchase.
Some manufactures include:
http://www.hammerheadscuba.com/default.htm
http://www.diveriteexpress.com/
http://www.northeastscubasupply.com/specials/bp_famous_specials.html
http://www.salvodiving.com/backplates__wings
http://www.deepseasupply.com/page12.html
http://www.halcyon.net/
Unless doubles are in your near future, IMO go with a back inflate BC. You can find these ready to dive for $200, and sometimes less on Ebay every day, and if you are diving Singles in a rec environment I can not think of a compelling argument for the BP/W.
I had a buddy (Dimitri) who purchased a Halcyon Eclipse due mainly because of a deal he found, but also because of the SB BP/W hype. He was so impressed with the BP/W system that after a couple dives he sold it, and went back to his Balance Back Inflate. And his system was what most consider one of the best BP/W setups.
Not to say that the BP/W system is not great for a lot of divers, but he just did not feel much if any benifit for single tank diving, and he is not alone in that opinion.
If you have not tried a good BackInflate BC, I'd highly recommend doing so before spending the $$$ on a BP/W system. If at that point you have decided that the BP/W is they way you want to go, than plan on learning a lot more about them before you make a purchase, and $400 is about as cheap as I've seen one new with cam bands, and ready to dive.