I have a cobra, same model and I love it. Switched the color to just blue and it looks sick at night. This thing will go off if your on the other side of the hill and the cop isnt looking in your direction. Put it up higher though, right under your mirror, and see if you can get it level, it will detect much better. Its also better up higher so the nose of it will go over the hill faster and be able to detect more cops quicker.