I bought it at Wal-Mart since the instant I saw Radar Gun I was interested, it was just $30 so I decided to give it a try :P I went out in a straight stretch and done a test. I got my friend to point/trigger it and I stayed 20 MPH in my car. I got back and the gun read 20 MPH, it was accurate. Then I was accelerating to 35 MPH and as he held the trigger it was actually accelerating, so if you use it right its accurate but has alot of errors. You have to stay very steady while you use it. It's 10.525 GHz, so I figured it would alert X-Band on radar detectors but it doesnt? The passport didnt alarm, I even tried on a Crapara and it didnt. Is those GHz in X-band or what?