We used it at Otakon last year for Zhongi (the doppleganger in Escaflowne) and here is what we found out:
It's bad for legs. It sticks to itself and rubs off even after having been sealed.
You need to shave right before putting it on or it will give you a painful all-over wax job.
You need friends, to put it on and take it off. Lots of friends.
It's horribly messy and takes forever and a day to dry.
I'd avoid using it, personally, and not because of the nature of the convention but the nature of the beast itself.
So, er, yes, it's been done. I think he was the most lightly clad person at the con. (costume = 1 speedo LOL)