Went to Mufflex today and got the DOD14M on my 2011 Regular Cab Express, was actually considering the DODM80 but decided to play it safe. First the muffler has a nice rumble outside. Acceleration has a real nice deep sound. Inside at highway cruising speed I have little to no drone in my opinion. I have had MANY Mufflex systems on my cars and our family. I will say this is an aggressively subtle. Great combination for someone who wants some aggressive sound but can still easily carry on a conversation in the cab.