Nick: I do still use the Weezle Extreme Plus with a thin Under armor shirt underneath. Mostly to absorb sweat. On longer duration dives, I also use a heated vest. The Weezle undergarment is bulky and requires extra room underneath. It also requires more suit gas to work well. Thus more weight on your belt. While it is a good undergarment, the new DUI undergarments get good reviews from my friends who dive them and deserve a look. Peter