I have a W1 7mm suit. I love it, it is the best wetsuit I have ever owned or used. As mentioned before the seals on it work very well and it keeps the water from moving around, which keeps you warmer. The draw backs to the suit are obviously the cost, if you have broad shoulders, you have to have a buddy help pull the suit off the shoulders, or you wind up looking like a retard in a straight jacket in the parking lot trying to get it off yourself. Another issue i have had is the collar and neck seal is very stiff, and a little bothersome at the surface, other than that I love the suit. Wish i have bought it sooner.