After I'd been riding for 15+ years, I got severe pain in my left knee one day, after a long ride. It took most of a week to go away, and came back (with a vengeance) the next long ride I did. Somehow my pedaling was wrong, suddenly, and I couldn't really figure out how. Clipless pedals made it go away, as close to instantly as is possible.
There are a lot of benefits to clipless pedals, and I wouldn't have thought much of "my knee pain went away" until I started experiencing knee pain. Otherwise, the zen-like connection to the bike is very nice, being able to pull the pedal up when you're stopped at a light but getting ready to take off is handy, and it's nice to be able to pull upward on the pedal in a sprint or a tough climb.
I use SPDs, on my road bike. Mine are very stiff shoes, with CF soles. I can't feel the pedal through them, and don't get hot spots. They're ok for walking in, but you would never confuse them for regular shoes. Still, you can scramble over loose rock in them to get to the stream for some water.
I also have a pair of SPD sandals, which are nice in the summer. I wear them when I bike to Magnuson Park for a swim. The lake bed has a lot of rocks and pebbles at the bottom, which poke your feet. The shoes swim well, and work on the bike. Makes for some happy days.
Originally Posted by
KBentley57
I would go as far to say being clipped in gives you ~ 20% more power utilization during your stroke.
Why 20 %, and not 10 % or 30 %? How did you get to that figure? It's extremely dubious; that's more performance benefit than you'd get from probably any other upgrade people routinely make.