I've personally had a lot of trouble getting clipless pedals to work for me so I've tried several different ones. The combination that I eventually settled on is Shimano pedals with the silver, multi release cleat. There is definitely a difference among the different Shimano models too. I haven't bought any new pedals in awhile, but both my wife and I definitely noticed a clear difference when we switched from 535 to 747 pedals (no longer avilable by the way). The 747's were noticeably "crisper" in both entry and exit.