I kind of disagree. I agree with the part about someone who reallly wants to steal your bike just picking it up, alarm, lock and all, but the average person who just wants to sit on you bike or some amateur thieves will think twice if they see a lock and then get the squeel of an alarm. Not only that, but generally bikes get quite a few looks from everyone as they pass by, so an alarm going off on a bike would generate even more stares, (most people don't expect an alarm from a bike) and therefore might disuade a would-be lock breaker. Even if my kryptonite has saved my bike once, it's worth it, and besides, you'll never really know unless it fails, right?