In my group (there's five of us that are tight-knit), I am the unofficial 'best' DM. All but one of us have the ability to, but each of them has quirks that at least one player doesn't get along with.
I prefer to play, just because I've DM'd for so long. I'm trying to work on a 'Mercenary' type game where we rotate DM's every session, and when it's your turn, you come up with a job for the other four players to go on. We'll see how that works...