Clipless. It is what I got used to before commuting, I have never had a problem unclipping in time. Sure, every now and again they can be a pain but I would rather deal with them than not have them on. I am going to switch to mountain SPDs with a platform on one side, just to make errands easier. Best of both worlds, right there. Also, if I really got into a problem and had to start walking, it is easier in MTB shoes. I leave a pair of shoes at work (or I transport a pair in my panniers if I need to).