Have you ever heard them? THEY ARE LOUD!!!!
Did you hear that?

You will have trouble hearing much after you spend time in a
car with doze babies. Again I say, THEY ARE LOUD!!! I don't know if you are talkin' 'bout the header mufflers, or the true mufflers, but seriously, they sound cool but they are really loud. Just last fall I sold a '80 Malibu that was gonna be my project car ('til I wised up and got a Camaro). The guy put a 350 in it w/ 1 5/8" full length headers and put the header muffs on there. It was very loud. As inconsiderate as I am to my neighbors with my exhaust/stereo, I felt embarrassed about how loud it was. He just kept revving up the engine to show it off. Then I would look around to see how many neighbors were looking out their windows. It takes a lot for me to care about what my neighbors think, but that was a lot. Just my 2¢. Some people think louder is cool, and that's fine. Just not all the time.