I've used my K40 with a V1 and a Bell in my car at the same time. One of my side-by-side tests was for about 6 hours from SF to LA. As far as forward looking performance, the K40 performed as good and sometimes better than the others. The long range detection from my front K40 sensor is basically unbeatable. Shorter range peformance was very similar betwen the various detectors.

And no windshield mounted detector came close to beating the dedicated rear sensor. The K40 is not just a pretty setup.

Mounting position however is critical. The first attempt at mounting the front sensor ended up with very poor performace. The 2nd and 3rd attempts got me significant performace increases.

-mick