For my driving, here are the results I get having now my R32 and also for my GTI - my driving habits were identical. Note my GTI is remapped to 240BHP.
GTI R32Overall Average 26 23
Town Driving 18 to 23 16 to 20
Motorway (75 to 80mph) 27 to 30 27 to 31
Thrashing who cares who cares (oh the sound of the V6

Miles on full tank 260 - 320 260 to 300
So, from owning an R32 for 9 months to a GTI for 4 months and back to my R32 again I notice as near as makes no difference to my fuel bill. I would say the R is costing me at most an extra 5er to 10er a week. Well worth it for the 4WD and V6 soundtrack.
Now I dont want to start any arguments here but all I can say is having owned both long term I can tell you one thing for sure. The GTI is more fun to drive. End of. The R32 is amazing, the GTI is amazing. They both make me smile, but what makes me smile is different for each of them. If that makes sense. Over in N Ireland we get lots and lots of rain. The roads are always slippy especially at this time of year so 4MOTION of the R32 is great.
The GTI and R32 are both highly desirable and as I have said before in an old post it is nice that we have both to chose from.