It flows very well, but its going to be VERY loud with their X-pipe, especially if its an offroad pipe. In fact, it would probably be ear peircing loud. It would get on your nerves for a daily driver, I know for a fact it would be significantly louder than my setup. (offroad x, 2 chamber flows).
In my personal opinion, half of me thinks the loudmouth sounds bad@ss, and half of me thinks it sounds like bubbling, popping metallic blobs of ***** being spewed out a shotgun. It sounds mean, but it blunts the sweet symphony of the Ford 4.6, and makes it sound more like a GM truck. In other words, sounds like something of big displacement, but kind of in an annoying way.