to be completely honest with you all, fuel ecomony is not what i would expect to be a prime concern for a GTi owner, as it is a performance car, not a ecomonical car.
I have a mk3, as you know which my girlfriend uses to go to work in as she does a lot less miles than me, so i use the more ecomical 1.4 astra.
And the mpg i get out of my mk3 16v is more than exectable for a car of its stature!
Mrwotto