the SE exhaust!
As far as I'm aware the only diff is the end mufflers are different to offer more growl and the SE is in 3 sections while the non SE is one piece. I wished the shop good luck with a message they may have a tough time finding a buyer at that price and they came back to me with a message of saying, 'good lucking finding another one'. This is true as the RS6 is super rare up here but there is no way I'm paying that much!
I'll look at local options for a more open muffler to give my RS some more sound!