Just left with a 6.2l Yukob sounding like a v8 is supposed to. Did a highway run at 75mph. The Magnaflow they recommended put the perfect amount of growl into wide open throttle with little to no noticeable drone at low rpm in 4 or 8 cylinder mode. This is the 4th or 7th time in 20 years these guys listened to what I asked for and nailed on the first go.
Need muffler/exhaust work? Go here everytime.
Update: did a 2800 mile trip and no issues with the tone. Quiet cabin, until you mat it. Then, yep, the appropriate amount of get-out-of-the-way growl.