Clipless. Once you get accustomed to pulling as well as pushing it gets hard to go back. Why let a whole muscle group go to waste?

It does take a while (and one fall) to get used to them, though. Just put the bike on a trainer and you have all the risk free practice you could want. I find them particulalry useful on hills. Riding platforms now makes me very uncomfortable, like riding in a car without a seatbelt.