I'm two weeks into driving my HCH II and have adjusted to some of the "special" behavior such as feathering the gas pedal, easing up hills, etc...(haven't tried increased tire pressure)

I live in the 50-60 degree F SF bay area and this morning was able to get around 46 mpg on my 11 mile commute. That included 3-4 autostops on city streets. I'd say my commute is about 60% highway, 40% city street... nothing over 60 mph.

But that 46 could have easily been 38 given the traffic flow that varies every day. When in city driving it all depends on number of stop/starts, you ability to keep a steady speed, terrain, etc... It just all depends. Overall, I'm doing about 41 mpg in our mild climate with a mixed driving environment.