I purchased this because of the ratings it received which were equivalent to my Beltronics RX65 radar detector. I placed it on the auto dash next to my reliable detector that I've had for 4 years or so just to see how accurate it was. It rarely ever detected signals and when it did "whistle", my Beltronics didn't. I was even next to a police car and it didn't even recognize the Ka band that the other gave loud and clear. I was going to give this as a Christmas gift, I'm glad I tested it out beforehand. On a more positive note, I sent it back and was promptly refunded.