I have a Cressi Competition and I'm pretty happy with it. I've used it in fairly cold water -- e.g. 2 hours of free-diving in 44 F water and sub-30 F air, 2-hour snorkeling sessions (no deep dives) in water that was right at the freezing point etc. I hate to get cold and I found the suit to be plenty comfortable on all those dives. Note that I'm a whimp when it comes to cold -- I wear a Tilos 3-2 jumpsuit in the heated pool when I work out.
The Competition is very warm, fairly comfortable and pretty reasonably priced. On the other hand, it's not Yamamoto rubber or whatever, so my buddy claims that the neoprene will get crushed thinner over time. My only other criticism is that the straps on the farmer-johns are a little flimsy -- I'm afraid that I will tear this suit some day, but it hasn't happened yet.
I also use the suit occasionaly for SCUBA, but the neoprene is so compliant that it thins out considerably at depth and I tend to get a little chilly on deeper dives.
In retrospect, I would have paid the extra to get a Super-competition.