I got in a 20 mile ride on Monday with the "M" spd on the prosthetic side and a regular spd cleat on the right, "normal", foot. It was awesome. First time I have been clipped in on prosthetic and easy release. I am 59 and I am strictly a recreational rider. I don't sprint or try and increase my workout. I ride relatively easy whether I am on our tandem or one of my 1/2 bikes.