We use them in the race cars and in the chasers. Theyre the best thing since sliced bread. no more wondering where the heck everyone is. One thing though if you are using a lowrance GPS you need to make sure the coordinate system is set to the same as the SPOT so you can see exactly where they are. I think that the Lowrance default is degrees/minutes and you need to change it to just degrees. We broke once under some powerlines and couldnt get any radio transmissions out because of the interference, we hit the help button on the SPOT , our chase crew got the message and found us in no time flat. Check if there arent any coupons. Last year they gave out coupons which made it really cheap.