Just installed this thing (finally). It was a lot easier than I thought it was going to be after reading the directions-- it probably took me 60-90 minutes altogether.
My concerns about the loudness were unfounded; as someone else stated before with the throttle at 0-50% (which is the majority of my daily driving) it is indistinguishable from stock. When getting on to the highway it has a nice growl, which I don't mind.
I was most concerned about the existence of a drone, but there isn't any.
2012 SE Sport 5MT 203A, Tuxedo Black