After owning 2 GTI's both DSG and now my 3rd also DSG lol, I would say that it depends all on the driving and how heavy your right foot is.
I can get between low 20s and mid 30s local driving and on the motorway, I can get high 30s. Again, all depending on how aggressive you drive.
Love it and it shall love you back haha, always smiles per gallon with the GTI
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