I have been using an Ironman Triathlon "Stealth" full wetsuit since 1997. Most of the time I use a Beauchat hooded vest beneath it, this solves the problem of a zipper that allows in some water (but typically not more than most other back zip suits), and the lack of a hood.
I like it, it keeps me warm, the mostly smoothskin exterior is hydrodynamic, and the flexibility in the arms and shoulders is awesome.
Is it a "perfect suit" ? No, but it gets me closer to what I want than anything else I can get off the shelf.......
I have also been interested in the newer designs that have come out in the last year or so that are a 2pc design, since this will alleviate the zipper issue, and they are reported to be even more flexible in the arms and shoulders than older models like mine....