I've had a Valentine One for years. It's a good unit, especially nice to have around for mountain passes where the cops often are driving towards you with the vehicle-mounted radar. You often get *minutes* of warning before they pass you. Having the arrows to locate the "threat" is very nice also, can't imagine doing without that feature now.
I don't use it much around home though, this area is almost 100% laser now, and I just don't speed that much in my Mazda. Now that I have the Boxster, I may need to rethink.