So, I've been driving my car for about 2 months now, and I still don't have a clear picture as to the car's gas consumption. Off the lot, with unknown gas and new engine, I managed about 220 miles and put in 10.6 gallons (why, yes, I do keep a fuel log). That's about 20.8 mpg. It crept up slowly over the next few fill-ups, with mostly the same driving habits. On a week when I drove a bit out on the highway, I got about 25.9 mpg! The last fill up has been disappointing at 20.8 mpg again.
The window sticker says that I should get about 20 mpg on streets and about 30 mpg on the highway. The GTI is one car where having a manual yields less fuel efficiency than driving the automatic, which in the GTI's case is the DSG - a "manumatic" type transmission where you can control the up and downshifts. I opted for the old fashioned stick shift.
My current average is an inferior 22.7 mpg, but then again, I blame my somewhat heavy foot. It has been a while since I've driven a little sporty car, so I'm happily zooming around - not going much over the posted speed limit, mind you, just getting there quickly. One benefit of living in Florida is that gas prices seem to be lower than in California (less taxes, but then again, they have a lot more toll roads here), and in Orlando they still sell 93 octane gas, as opposed to Los Angeles, which I believe now has 91 octane. You get a few extra horses from better gas. Currently, Chevron premium gas, which is of better quality, or so I hear, is about 3.619 dollar a gallon in a few stations (this is the low end of what I've observed), and prices have fallen considerably the past few weeks - at the beginning of September the same gallon of gas at the same station went for 3.879 - about 7% cheaper!