I don't watch reality shows, or television in general really, but I'll take stab at this anyway. I'd probably end up being the megalomaniac, the one who thinks they're better than everyone else and would be so assured of my victory as to not even put in any effort. I'd also believe myself to be the sexiest one of the bunch, even though I'm kind of ugly.
Those shows have people like that, right? That's just good television.