That is not my experience with the 2013 RT, Jack. I like the sound of my RT with the Cat (primary muffler) removed, but that's NOT why I did it last winter. It was to eliminate additional heat (in addition to the "improvements" I'd already made). Now that we've had a few very hot days this Spring, I have to say that it has indeed made a difference in rider comfort.
Furthermore, I used to be able to remove my gas cap and actually watch the fuel boiling inside the tank. Since the cat removal, I have NEVER seen that happening again. And the occasional smell of fuel vapors is completely gone since the cat removal. Though removing the cat is only one of several things I've done to mitigate the excess heat problem, I consider it to be one of the most significant.