I have the 10 series on mine and it is not loud and obnoxious. Its not all that much louder than the 40 or the 44. It has a constant sound through the rpm band where the 40/44 kind of die off around 3800 rpm. I'm currently running a banks header, 2.5" pipe and high flow cat and honestly the glasspacks that I had on my 95 were louder than my 10 series.