i use powerstraps or whatever they are on mks flats. the straps are not tight on my feet at all, just enough to keep em in the pedal. i ride roads, in town, commute, ride trails, ride anything with this setup. i mainly got them to keep my feet on the pedals, not to feel "clipped in". i found when riding off road or when changing gears while applying power, a foot could slip off the flat pedal. the powerstrap has pretty much prevented slipping, plus i can get out nearly as fast as no strap at all. wins for all