Have now driven about 200 miles since install-my Indy said these fit better than most gloves (2.5 hours labor and precautionary went ahead and installed new manifold gaskets.). I previously had a set of oem new mufflers modified and ceramic coated by FD motor sports, Softronics 93 octane ECU mod and Fabspeed black chrome pipe exhaust tips but decided to finally do the “full Monty”. I shall presume that the ecu has now ‘learned/adapted” at this juncture. The sound is just fantastic, and from a guy who just returned from a bucket list travel with a great friend for ED of a Miami blue GT3 and drove 2500 miles in 12 days through France (Champagne, Burgundy), did the LeMans race, Nurburgring, Mosel, etc. Engine just sprints and feels freer. Burbles on downshifts (manual, no SC or PASM equipped). No, it doesn’t feel like a JATO system was installed, but butt kick and 4-7k just screams. Quite pleased.