During our recent jammer test I had a friend come out with his Whistler Pro-78SE and we decided to do some quick testing. Standing approx 50ft away from his Mustang GT, I started pulsing the Whistler with the Ultralyte 20-20, headlight, center mass and nothing would trigger the Whistler. Backed up another 50ft to approx 100ft, shot again, nothing. Went back to 50ft, shot the RD directly and sure enough, laser alert. Tried 5 times directly shooting the Whistler directly and it alerted each time, but nothing headlight and center mass. Although I do agree Whistlers are superior to a Cobra for instance, why not just invest the additional $150 or so and go with a V1, or higher end RD? Lack of knowledge I guess. The guy truly didn't even know what the different bands meant, or what to do when encountered so I gave him a quick lesson, although I'm hesitant to believe any of it stuck.
I then pulled up my vehicle running V1 + LI dual to run the same test for him. 50ft headlight, instant laser alert on both V1 + LI, 50ft center mass, instant alert both V1 + LI. Backed up to 100ft, hit the same areas and instant laser alert on both devices. Then decided to hit the side mirror for him, instant V1 + LI alert. Really put it in to perspective for him. He didn't have time to do some longer testing (2,000ft + that we completed on a longer stretch of road) and I don't know how well it would have performed, but I would be doubtful it would alert consistently to laser and I/O and the distance at which it would alert to even C/O.