Haven't really taken it for a drive, but was told by PPE and several reviews I've read that it's not noisy at all and just a slight increase in engine tone. Should be a minimal volume increase which is all I wanted anyway. Don't need or want anything loud. Folks has said they are getting 2-3mpg more. Not sure if that exaggerated or not but I will certainly post my results. I did this to clean up the engine bay and improve air flow...not for noise. Still thinking about doing a 5-Star Tune but not sold on that either.