Bit late to posting this, but last weeks trip to Ontario to pick up my Civic was pretty good real world comparison between two competing vehicles. Going to Ontario my VW GLI averaged 6.6L/100kms, coming back my Civic Si averaged 5.6L/100kms. The Civic only had 12kms on the odometer and was saddled with around 300lbs of extra cargo (136 beer and a set of winter tires and steel rims) that were not present for the GLI.
I’m keeping a keen eye on the fuel economy now in my normal setting back home. My Golf R this time of year averaged low 9’s, my GLI averaged low 8’s, and so far the Civic is averaging even better than those, too early to reveal the full numbers as I have only driven 160kms since my first fill up back home.