I've done most of my diving in water that is just way to cold not to be wearing a wetsuit (or even a dry suit if you have the option). One of these days I'll be diving in warmer water again and I might give it a go, I don't seem to get bothered by a lot of the jellies that other people do so it should work for me.
And here's a way to get it a try if your thinking about it - just tell the rest of you party that it is your 100th dive (it's customary at least in NZ to do your 100th in the nude, and they'll probably only catch on the 4th or 5th time you the excuse)