I have the TK cat back with the high flow cat. I dont have a video up yet but I can tell you that its a great sounding system. Originally, I had it installed withOUT the high flow cat and there was no drone at all. Got the HFC and it got louder and the drone is audible but nothing that cant be toned out. You can definitely feel the power gain when you step on it which I love. I will try and get a video up but (K)(I)(A) has a drive by video with his TK catback. Search for it!