Another Xterra owner here. I wore a Vortex 3 sleeveless for my first season ($99 deal!) and it was great. I've lost enough weight that I could justify a new suit for season 2, so I went with another Xterra and got the Vector Pro x2 (also sleeveless). LOVE the new suit. I got a deal on it ($200) and it is definitely worth the $100 upgrade from the Vortex 3. The neoprene is more flexible, the suit is more articulated around my joints and my waist and it fits like a super tight glove. I've only worn it once so far, (second time is tonight), but I was impressed.

Around here, a wetsuit is a necessity. Early tri's have water temps well below 60F some years (like this year!). Our water doesn't get all that warm either, so a wetsuit will remain legal for the entire season at most venues. Since I overheat easily, I stuck with sleeveless so that I could still bear to wear it in water approaching 72F. I suffer a bit at 55F, but I survive.