I still like a little rumble, but then I'm younger than many here.
Funny thing, when I first bought my jeep it needed a muffler so I put a flowmaster on it. Cut it off and threw it away after 3 days, ain't never heard nuttin sounding worse than a stock straight six with a flowmaster!
As for the RV, mine is an 08, with that lousy DPF, which has all ready gone into limp mode once a year or two ago, and I had to go 20 miles on the highway to cummins for a forced regeneration. Yuk.
I've a line on a company that reprograms the ECM's to eliminate the regen cycle, guarantee's no codes. As soon as I gather the cash, that garbage can muffle is going to the trash, replaced by an Aero XL and 4" polished pipe, along with a reflashed ECM and 435HP!