Remember guys, that the sound that each person is looking for is for that person and that person only. That's one of the reasons there are so many exhaust systems to choose from. What sounds good to me may not to someone else.
Headers can have a little to do with the note of the exhaust, but like Chris Wilson (my good buddy,,,furry buddy)!, said, the muffler (or lack of) has the biggest affect on the tone of the exhaust.
As for the cats, I hate em, but I must admit that they are good for the environment. Like they always say, the good things in life will sometimes kill ya!
Barn Man....