Anyone tried this?

crankycrank

This alarm may be different but my experience with motion sensor alarms for bikes, especially the cheap ones such as this, is that they tend to go off constantly due to the bike being bumped or moved by wind even. Rain also tends to set off the alarm or render it useless and the 80db volume is really not that loud plus the fact that most mfrs. tend to give a very optomistic rating for sound level. It also looks as though it could be disabled fairly easily.