Have ridden with them on road bike before I went clipless and now use them on commuter bike. Very comfortable and pretty efficient as well. You can still fall over if you roll up to a stop and forget your shoes are hooked into them.
EDIT: I prefer them to toe clips because I have size 16 feet and with toe clips could never get my shoes centered over the pedal. With PowerGrips, this is not a problem - feel like my foot is properly positioned.
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centexwoody
They're beautiful handsome machines that translate energy into joy.