Been riding SPD's for a while and I think that I will be sticking with them (for now).
However, I have knee pain. One suggestion is the position of the cleat - fore and aft. I used to have them with the spindle pretty much on the widest part of my foot, which I "think" is too far forward.
Every picture I see they are about an inch back from this position. A quick test ride tonight felt good.
Now just after picking your lots brains.
Cheers

