I'm in the smaller group of people that isn't a fan of them. I bought them to use with all the shoes I use to ride with - well turns out my shoes vary so much in size that I was stuck wearing one pair of shoes to ride in. I already had clipless shoes and pedals, just can never get them adjusted to not cause outrageous knee pain.
Now I don't run either, and I can wear any shoes I want. Will be trading my power grips off to my roomie, who loves them.