I bought the XRS version of the Cobra radar. I don't know if it really work that well yet bc it's still winter and there's a lot of obstruction around that may have block some signals. Although I did pick up some Ka and K bands when squad cars come straight towards me. What really annoys me is that from time to time, the radar would not come on!!! I'll have to call Cobra to see what's going on. I hardwire it to the stereo power line of my car. Any ideas?