I am going with the Bassani X-muffler system. I want a more sophisticated smoother tone and my experience is that having the muffler in the middle of the car with long pipes after the muffler will give me that. Having mufflers at the end of the pipes always sound rough and raw and harsh.
2010 GTRR in 5.0 Magazine [http://www.mustangandfords.com/featured-vehicles/m5lp-1212-2010-ford-mustang-gt-rr-total-fabrication/viewall.html]
2015 White SC, PP, etc....