I just bought a used 05 in good shape with the WB Aluminum Pro exhaust on it. My buddy has an 05 with the Big Gun EVO R full set on it. When riding them back to back my buddies bike is noticably faster (revs faster, more hit, etc.). Both bikes have had no engine work (stock) but he has the longer header that comes way out around the radiator hoses while mine is shorter like stock. Could this be the difference in power character or is it the Big Gun vs the WB? ...or something else perhaps. My bike is a lot smoother with almost no hit. The bike is still fast but it doesn't get the adrenalin pumping quite like my buddies bike. What gives?