Been using the Fuelly app for 2 years now, and my average is 6.8 liter per 100 kms.

 

I have an 08 and with the crappy 14" steel rims this thing came with (and did Honda actually do that or should I go beat up the former owner)? .... but anyway, tiny little tires, my first tank gave me 38.5 mpg which is more city driving and trying to get used to that grabby clutch and first gear that seems to redline at about 10 mph. Second gas check gave me an incredible 44.6xxxx mpg. I know I drove a bit more on the highway but that was pretty good.
3rd tank!!! So, I did quite a bit of highway driving, probably 75% and I have 320 miles on the clock, yet the fuel gauge is just a touch below 1/2 tank. So depending on how accurate the fuel gauge is, I could be looking at beating the 44.6 mpg pretty well.

Disclaimer: Half way through the mileage on this third tank full, I swapped the 14" rims out for some 16" 205/65R and the car drives like a million times better, but it will throw off my actual mileage slightly. I'll post once I fill it up again!