i think that powergrips are the perfect solution to the problems associated with clips and straps and have written about them several times here on bikeforums.

here is a rehash:

the biggest problem with clips and straps is that, unless you tighten and loosen every time you put your foot in or out, you will either have the straps too loose and less effective for pulling up or the straps too tight for easily getting in and out of (and more prone to obliterating your shoes). there is certainly a middle ground, but it's never ideal. with powergrips, you put your foot in (and take it out) at an angle. the strap is loose until you twist your foot to straighten it out, which then tightens. so long as you keep your foot facing forward, the strap will stay tight and effective for climbing and the like (though not as good as the best clipless setups). when you want to get off of the pedal, just twist your foot and remove. it's extremely easy to get out. i find them to be far more effective than a compromised (read: loosened so that you can get in and out of them easily) clip/strap setup. they also don't eat your shoes as quickly.

as for problems. the hardware that comes with powergrips isn't the best. if you weigh a lot, or have larger feet (which means that more of your foot hangs over the sides, putting more stress on the hardware), you may have problems with bending or breaking the hardware. i'm quite skinny (140lbs) with size 8.5-9 feet and haven't had issues. well, i bent a bracket in a crash, but that's to be expected.

in any case, i'm a big fan.

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