I'm also looking for the "perfect" catback and have just about selected the Borla "S" type as it isnt too terribly loud at idle but roars under WOT. Just remember after you install longtubes the sound doubles easily if cats aren't used and usually something that you loved before the headers ends up being something you despise later. So since i've been in the position before on a another long tube headered vehicle i plan to keep racing cats in my exhaust system. Who cares if it loses 3-5 rwhp I want it to sound nice..
2014 Sterling Gray Gt 3.73's, MT82 Trans
, Forgestar CF5's /w Michelin PSS tires, JLT Carbon fiber CAI, Bama 93R Tune, Borla S Catback, DSS Alum driveshaft, BMR springs, LCA, UCA, UCA mount, Panhard, Panhard brace, LCA Relo brackets, Viking Dbl adj shocks, Strange Adj struts, MGW shifter