Starting next week I will be commuting to work by bike. I've spent the last two hours looking for a bike U-lock. I haven't found a single lock that someone hasn't complained about for jamming up on them and becoming worthless (or worse, permanently locking there bike somewhere). It seems all the key locks stick and eventually don't turn at all. And the combination locks seem to fail over time too.

I don't need anything super-duty. I'm not in a particularly crime-ridden area. I just need something stronger than a cheap cable that WON'T FAIL on me. Maybe a U-lock isn't the way to go. I haven't looked into chains. Do they fail often?

Thanks.