I love the clips too. When I used pins I would get stuck a lot and even more annoying, my thread would get caught around them. Since the bindings are roundish it didn't happen so much with them. Plus it holds the binding flatter than pinning.
eta: I've never used clips for machine stitching the binding on (which I've only done once so far). I'll have to try it for that. I always hand stitched binding before.