I have C-skins wired, 6:5 with integrated hood, and it is the warmest wetsuit (or rather a semi-dry) that I have ever had. It is my first suit with integrated hoody, and I really like it. There is much less water pooring down the neck when sailing in waves. Have been using it down to -3 C (air-temp) and it works great.
It doesn't pull more on the jaws than the hooded shorty I used to use under a regular wetsuit. The hood is also thicker and warmer than separate hood or hooded shorty is. Guess you can sail with the hood off, you want to, but I usually change down to a 5/4 without hood when the wether permits.
