I tried riding our local 'cross course in mine (performance version, but essentially the same pedal) on a slightly muddy day. Wouldn't do it again. The design just couldn't clear the mud out, and the flat side has enough "teeth" and size that I think it would hurt quite a bit more to bump into them than a Crank Brothers or Time pedal on a mount/dismount/carry situation. They're fantastic pedals for my commuter/errand bike though.