I had a 3.2 TT from 2008 to 2011 and it was a superb car and engine, albeit I had the manual.
The fuel consumption I thought was very respectable.
I could hit around 35 mpg on a long distance run quite easily and high 20's around town.
I changed it in 2011 for a TTS which has the 2.0 litre turbo so I thought that would be more fuel efficient.
To my surprise it was slightly worse !
Around 32-33 mpg on a run and 27 ish around town.
Ran it on standard 95 ron and it was fine.