Returning somewhat to the original question... I used to have a Valentine-1, and while using it I never got a ticket. However, the damn thing would be going off all the time, even in the "advanced logic" mode. Then, when I once valet parked my car, the valet stole the V-1. Grrr... Since then, I haven't replaced it. I've found, instead, that my car is a more quiet, calm place without the damn V-1 going off all the time.

Instead, my current strategy is that on local roads that I know well, I know all the places that I tend to see cops and just drive slower there. And, when I'm somewhere I don't know, I try to keep my speed close to the "average" speed of drivers around me. Consider I-45 from Houston to Dallas. The speed limit is 70mph. The average speed is probably 85mph, and if you only go 85, you'll have 18-wheelers blasting past you. I've done this drive both with and without the V-1. In practice, with enough road traffic, somebody way up front tends to see the cop and will slow down and you'll be thinking "why is the traffic slowing down here?" until a mile later you see the speed trap. The V-1 had much less value than I would have thought.

Admittedly, I had a lot more fun driving on the autobahn when I was in Germany where I could focus my attention purely on safety issues rather than scanning for police. When I'm back home, I've just forced myself to generally drive slower as I get no joy in fighting speeding tickets.