Hey all. I installed a new Magnaflow Competition series cat back on my '13 6 speed 392 today. I'm glad I went with Magnaflow because it sounds awesome! Nice little rumble at idle and while lightly accelerating, and F-ing balls to the wall at WOT! And the drone. What drone? Took it on the highway, top gear, 1500 RPM give or take 100-200 RPM, windows up, windows down, no drone, NONE. And the down shifting, sounds very, VERY cool. Great exhaust, especially because there are so many out there, I'm glad I made this choice.