My 03 A6 2.7T Sport I bought new is long in the tooth but just over 100K on the clock and we still have an ongoing love/hate relationship. Right now it's on my sh*t list due to a nagging front end vibration that can't be located AFTER I spent money for new control arms, etc. all spurred by a new (used) wheel purchase. I bought my son't old (DTM) RS4 wheels and stuffed too wide PilotS4's under it. The venerable 2.7T is absolutely bulletproof although I have replaced a cam chain tensioner, leaky valve seals, and of course coilpaks and practically every movable piece of plastic switch has fallen apart.
I almost bought an RS6 not long after I spent $6K to replace the turbos in the A6 - caused by a mild chip tune (so I put in KO4's), but my Audi mechanic, who played HS football with my oldest son, helped me see the light and the true cost of maintaining the RS cars. My son, a former Audi Master Tech (now @ Mercedes) has a 2001 Nogaro Blue RS4 Avant as his DD.
Short list:
2020 in my sig
2003 A6 2.7T
2009 Polaris 500
wife: 2008 Imprezza
I'm still half heartbroken over selling my 04.5 5.9L 2500
P.S. Two of the bays @ my mechanic's shop today.
View attachment 5386