I really enjoy the sound of my SLP Loudmouth 1's despite the "ass cheeks slapping together" comment from earlier. I'm running the SLP catback system w the stock exhaust manifolds and the stock catted H pipe. It screams at full throttle but is pretty mild in my opinion when cruising around, I don't get any drone on the highway, and conversations in the car are had w ease. Now if you pair these mufflers up w a catless H/X pipe you will get some ass cheek slapping sounds going on. I've always felt that despite the restrictive nature of a catalytic converter it helps to smooth out some of the raspy nature of aftermarket exhaust systems. Before the SLP catback I was running a Flowmaster 40 series system and I just felt it sounded way too tinny and hollow for my taste. The Flowmasters sound much better on old school muscle cars like my 66 Mustang IMO.