I had look cleats on my comutte road bike for ages but decided this winter to swap to spd with mtb shoes so the cleats recessed, there easier to walk in but more importantly when you put your foot down the tread on the shoe gives you alot more grip, which in icey conditions and wet is what I was after. The other bonus I found was the clipping in and out was easy, especially if you missed the the clip in point when you pulled away, you could still pedal without being clipped in properly, great at islands or lights. I had a few moments with my look cleats faffing around to get clipped in at rush hour, not good. I wouldn't go back now for comutting at least. But saying that I've done over 40 miles none stop and felt no discomfort, as some say they cause hot spots on your feet from the pressure on the foot from small cleats on spd's. But I haven't found this.