I remember reading on Roy's site that a Detector thats been in operation for an extended amout of times vs. one that has been on a couple minutes will not perform the same. He states that the detector thats been on for a while will have better performance. I don't think he got into specific detectors, I think he meant this for all detectors in general if I'm not mistaken. If so, how is this possible? Is so, is the performance gain considerably noticeable? Thanks.