I drive through an area where a guy is running a big base station but I haven't heard him for a while. Today He was on the air and I made contact with him. He said my radio sounded good and we figured that he was 20 miles away.
I thought it was pretty cool although the guy is often a nuisance because he just blabs on and on plus he's near the interstate
I also made contact with another car with a mag mount antenna. Not sure of the brand but it was one of those with a black coil about halfway up the shaft. Not a big one, probably a cheapie. I could only hear him for about 1/2 mile before I outpaced him and his radio. The antenna was mounted on the roof towards the back.
I'm sure he can't be very happy with it...