We have had ours on our last two Chevy-GMC trucks, about 10 years now, and it has helped us too many times to count. We don't have cell phone coverage at our NC home and the OnStar works right up to the garage door. When our power is out, we can report it from the truck. Our family has contacted us in very remote parts of BC and Alaska and we had a garbled message from friends one time that let us know that something was wrong, even though we couldn't really hear them. We have made motel reservations in a blinding snow storm, found a vet for our dog,....on and on. That said, it doesn't work everywhere but we don't leave home without it. lizzie