Maybe there is a reason it was returned before.

Radar detectors don't do anything anyway. I had a $120 Cobra in my eg. I was going down the road and I see a cop a 1/2 mile ahead, who is obviously sitting there clocking people. I roll past the cop, looking back and forth between his radar gun and my ever-silent radar 'detector'. Not a single peep. Every ticket I have ever gotten, cop was using a laser gun. It's nearly impossible to detect a 40mm wide band of light, especially when they are trained to point it at your front bumper (where it's highly unlikely that your detector is mounted).