Well at the time I started riding clipless 10+ years ago Crankbrothers were known for clearing mud extremely well but being fragile. Shimano were know for being indestructible but clogged with mud easily. Time were both indestructible and cleared mud nearly as well as Crankbrothers so that is what I went with. Now all my bikes are Time, I'm use to Time, and I have no reason to switch to something else. The only real downside is nearly everybody I ride with is on Shimano, kind of the default, so we can't swap bikes mid ride just for fun.