As soon as I put my catless downpipe and catback on, the burbles were VERY prominent, still factory tune. I'm on APR stage 2 now and STILL get all the nice crackles and burbles. Even get the "DSG" farts when I shift gears. Couldn't be happier with how it ended up sounding with just replacing the exhaust piping even though it's a tad loud right now.