Originally Posted by _OTZ_
I managed to get my SE down to 4.5L/100Km on the way home from work last night (52mpg) over a 30km drive. Found the sweet spot to be around 90km/h - I hate driving that slow, but I have become obsessed with getting a decent mileage out of this car. I will add a caveat that the my average is 5.4L/100Km on a 90% mostly highway drive. I'm happy!
The maximum mpg has been shown by at least 2 sources to be in the range of 40-45 mph (i.e. the sweet spot). You should be able to achieve over 60 mpg in steady driving in calm conditions at that speed. Not that there's many roads you can drive 40-45 mph without stopping for 30 km.