I just had the Magnaflow (11385) installed on my 3.5 and I am overall pretty happy with it. One thing I noticed is that around 2500 to 3000 RPM's, there is a pretty bad drone in the cabin area when the windows are closed (especially when the car is under load). When they're open, it's not as bad but we are getting into winter so my windows are going to be closed alot. After your exhaust has 'settled in', have you noticed that depleting at all? I am afraid with the current setup, my wife is not going to be extremely fond of it and I will have to go back to the stock and I am looking for a 'ray of hope' to keep it.