Radar detectors are strictly forbidden. The latest rage has been the use of speed cameras. It is generally understood that these are used more for revenue than to improve safety and there is an effort to ban them. Manned radar setups are well hidden and they use unmarked cars. BAC who cause accidents.
Cars are different too.
And, now there are many new Mitsubishis, Toyotas, and other imports. You have to really want an import. This makes the imports quite dear. Despite the duty, the dramatic quality advantage of the imports made them very popular. U.S. models are very scarce.