I've installed this alarm in two scooters/mopeds and it gives me huge piece of mind. It's both sensitive to movement, and very loud. The batteries last a couple months, and need to get swapped out from time to time otherwise it gets quiet, but it's also a good chance to make sure it's functioning when you switch out the batteries. There's a function that helps you find your vehicle, so that for me was an unexpected quality of life improvement I didn't intend when buying this. I think it's deterred one theft so far, since the scooter was tampered with, but still exactly where I left it.