I always use a pair of bike shorts. No problem with bunching, and while I may not be the sexiest beast on the beach, 1)I'm only in em till I can throw on my shorts n a hawaiian shirt, and 2) who cares? They dry fast, they're comfortable, and I haven't noticed a problem with heat exchange. On top of that I generally wear a skin suit and then whatever other suit is necessary for the water I'm diving in. THe skin suit makes getting into the other suit much easier, in my opinion. You just slide right in as opposed to trying to pull the thick neoprene on with it sticking to every bit of exposed flesh. All in all, skin suits rule.
Nate