Not a scientific survey, but after comparing detector use that I see in cars out west, vs here in Florida, I see a LOT more detectors in Florida. I always look at cars in parking lots / malls / grocery store lots, etc and after a few weeks here, I see a noticeable difference. I can only surmise it comes from extra enforcement. I'm guessing the eastern half of the US has higher use of detectors per capita vs the west.
Again, not very scientific.