Well, I now have a massive 265 miles on the car now, - but that will be increasing quite a bit over the next few weeks as I've got a couple of family trips from Cheshire to London and Oxford panned.
My long term up to now is.....drum roll......41.2mpg. Not brilliant, when my Scirocco (for the same journeys) was giving 45-47mpg, albeit with over 40hp less. Am I bothered.......nah,... for a couple of reasons.
1. With the mileage I have on at the moment, it's still factory fresh and feels tight as a drum. I expect once it properly loosens up over 2-4k miles, things will improve, and I seem to be permanently stuck in queuing traffic at the moment (which doesn't help).
2. It's been bloody cold ever since I've had the Golf (typical), at less than 8°C in the mornings, and I know from the winters in the Scirocco, that the cold weather does have a real good affect on MPG.
3. Even if the MPG stayed the same at 41mpg versus the Scirocco's 46mpg average, that's 5mpg difference so for my typical mileage, that equates to about £250.00 per year extra on fuel - not exactly a massive penalty for driving a 181bhp Hot(ish) hatch

, and that's always assuming the MPG doesn't improve, which I'm sure it will.