I'll +1 this as well. I haven't seen a single Rev round on this server as it is. Not that I've been here very long or anything, but still...
Anyway, I like Rev because the antags depend so much on teamwork. They fail a lot because of this, but when they succeed it's pretty awesome.
Oh, but you'd need to make sure it can't be selected when there's fewer than two, maybe three heads.