I've used one also, but found it didn't hurt my receive as much as it helped me get out.
BUT...
I was driving a Sterling truck and because of static and interference, we were not able to get out or receive more than a mile...sometimes 6 tenths of a mile. In my case, it helped a lot. If you are getting out and receiving, I have my doubts that it would not affect your receiving ability. In other words...I think it will kill your receive.