I used to like loud, too, I was the guy with Cherry bombs on my car

even then I preferred performance over noise, so once I did my research re exhaust, my car had a single three inch exhaust, rater than duals This makes better low to mid range torque, as opposed to high end power, and most car engines live their lives between 2-3k RPM, or did back then (V8 era)
this is an a basically stock engine of course, on a car with a 3/4 race cam, you want an exhaust more biased to High end power, to match the engine's power characteristics
nowadays I guess I've mellowed, my cars have stock, quiet mufflers, and I find it more restful and less tiring to drive them that way
I tend to prefer stock muffs on bikes, too, but the S40s muff sounds wrong, especially mine, that has a bit of a whistle to it
The Dyna muff, though, sounds ....right, on an S40, a little louder, but a lot deeper