Cat back exhaust (which one is the best, for sound etc)

It's opinion, every one seems in love with akrapovic but I liked oreca motorsport single exit system but that's manifold back, not cat back.
 
Don't have one myself, but from video's I've seen, the Scorpion gets my vote. Looks great too with the slash-cut tips for the 197
 
Don't have one myself, but from video's I've seen, the Scorpion gets my vote. Looks great too with the slash-cut tips for the 197

I've been looking to buy one soon and the Scorpion is definitely top of the list so far, seen quite a few videos and it sounds great!