Speedplay X pedals and Shimano road shoes on my carbon bike
Speedplay Frogs and Shimano mountain shoes on my titanium, more relaxed geometry road bike. I need pedal float.
I can't stand the "locked in" feeling of spds... although I started with them, used them for a year on my first road bike. I also had them on my mountain bike and my Jamis Coda flat bar road bike. In fact, I had the AA530s on my Jamis, as I thought I would ride without bike shoes occasionally. I spent most of the time trying to flip the pedals back over into the right position, as GoCard said. My knees hurt if I use spds, and I don't have "knee problems."