Radar Detector?

It was on,(stupid on my part) and laying on the floor. When he asked I just simply said no and he said ok, and that was it.. When I bought this one it was supposed to be undetectable, but who knows technology moves fast... I think as long as you turn it off as soon as you see the sign for the coops you'll be ok.. I looked at the redline too but I just couldn't see spending $500, this one was bad enough at 300 and something...