Hi, I'm fairly new to scuba, but I've learned a bit about BCDs very quickly. I got my certification using rented jacket-style BCDs. At the time, I did not even know about the other kinds, other than a vague mention of rear-inflation BCs, which my instructors assured us were horrible. From the very first, I hated my BC. It rode up and cut off my circulation or strangled me when inflated, depending on adjustment. I felt like an astronaut, barely able to move in the thick vest. Also, the Velcro cummerbund was a technological nightmare. I knew there had to be something better.
After a lot of research, including on this forum, asking questions and trying on BCs, I settled on a DiveRite backplate and wing. I love the freedom of movement, the simplicity, and the fit. When I later rented gear from the place I got my certification at, for some diving, the equipment manager was horrified. He assured me that "most people who try a rear-inflation or backplate and wing take it back the next day." I was made to feel like a complete idiot for even considering purchasing such a contraption. I was basically told the backplate and wing is all but suicide. Well... after some strenuous cold water diving in varying conditions, I determined the equipment manager is the moron, not me. The backplate and wing is so much better I cannot imagine going back to the jacket-style. Everything you do it easier and more comfortable, aside from the tendency to tip forward on the surface.
Those are my thoughts anyway.