It's a nice system . You might want to look at the Ford Racing Borla Sport cat back. I have it on my 16 CS. I had Borla Atak on my 15 GT. My 17 currently is stock . As you know its all about preference.
Exactly, it is all about preference. There is no bad sounding system out there honestly. Hit up YouTube for a few hours and just get a feel for what each brand has to offer. Pick what you like, not what others try to talk you in to. I personally am a fan of Corsa, but that's just what I used. I would be a fan of anything that sounded good.
You really won't get more performance from one brand to another, so that really isn't anything to be concerned with. Tone, loudness, and rasp are the three things that will differ brand to brand.