Even the best testers screw up sometimes. For its September, 1995, test of cheap detectors, Car and Driver threw a V1 into the mix, supposedly to show how much protection you lose by buying low-cost units. Unfortunately, the test range was sized for the weak performers; V1 maxed out the range at 2.4 miles on both X and K bands. No one knows how much warning distance it really offered because the testers had no room to measure more. Worse yet, the author simply presented the results in the magazine, with no mention that V1 performance was limited by the length of the test road, not by its sensitivity.
Throw the red flag when you see bar graphs running the full length of the grid. In that 1995 test, the readers came away with the mistaken notion that cheap detectors perform almost as good as the best radar detector on some tests.