I've got one and don't regret it, they are also coming down in price so a bit of a bargain for the laser alert and gps system in one. I have been targeted once on the m40 with a gun and the thing went crazy. I saw the men in blue before the device went off and its true unless your quick on the brakes you probably will get caught if doing a large amount over. The gps bit is great though, all those hidden ones are exposed and I have found the blackspot info usefull if a little too regular. If you can get one for less the rrp go for it, I seem to recollect just over 300 is the going rate in some places.