ive been through like 3 dectors areound 150 bucks each.. they are total junk. 2 cobras, 1 whistler. sometimes on the highway they will detect and warn you on time, and sometimes a damn cop car is like right beside you, adhead of you for a minute, or behind you and it doesnt do shit. if you really want something good try the top of the line cobras and Passports, or Escorts. anything below 100 is just toys.