In Horry County I was first using the stock antenna and the reception was poor at best. M 436hp was blowing it away. I then put on a Remtronic BNC 800 antenna. All changed, the SDS100 was keeping up with the 436HPcall for call. Then I traveled Horry and Southern Georgetown counties with great results with the Remtronic antenna. I was very impressed by reception while traveling in both areas. it actually out performed the 436HP at times. All in all it is a great improvement and I love the radio.