I'm so glad that we bought our driveway sensor alarm. What's nice about is if you're waiting for a delivery you know they're here as soon as they pull on the driveway. Also our mail box sits back in so the alarm also indicates when the mail arrives. Sometimes early sometimes late. I think sometimes they forget. It also helps out when you're not expecting company and they show up unannounced. At least you have the short period of time to get to the door when unexpected.