This Texas officer is very informative in allot of his videos on the operation of the stalker DSR2 radar he uses. I'll post others in the enforcement,technology tactics category. In this video he first demonstrates the range with the V1 by using his police vehicle and listening to the V1 alerts through his cell phone in the distant target car he closes in on a hilly road. Got about two miles of alert. Then on the second part of the video he uses the Stalker's instant on. Just shooting at the vehicle with the V1 in it. Boy, plucks him out and locks his speed in a second. No chance to react if you got singled out by this gun. See the instant on demo in the other category I posted.