Have you considered having an exhaust shop weld in some resonance chambers like AA has on their exhuast? It shouldn't cost much. I just wonder how it would sound.
Let me get this straight... You are swapping out parts designed by some of the top engineers in the world because some guys sponsored by a company told you it's "better??" But when you ask the same guy about tracking, "oh no, I have a kid now" or "I just detailed my car." or "i just got new tires."