I too use the generic under armor from Walmart. I have went commando plenty of times and really can't feel any difference between commando and under armor. The material is super thin and the things fit great, not too loose or tight. One thing though when stretched you can see through some of this material, so unless you don't mind mooning everyone be careful how you bend over putting your wetsuit on aboard the boat. The see through quality is a small price to pay for the thin material though.