I have a 06 FLHX that I recently installed V&H Dresser Duals with Oval Mufflers. I also installed a Dynojet kit and Bigsucker. I have the bike running pretty sweat but a local bike shop told me that the only way to get it running perfect is to install power cones in the header pipe. He said that I don't have enough backpressure and that will hinder performance. I did have these cones in my 01 Fatboy with V&H Straightshots. What are the pros and cons of running cones in the header pipes. I don't mind spending the time or money as long as they are worth it.