I mix city and highway I guess...and I dont step on it too hard most of the time...was getting about 25 or 26 before sri, now about 28 or 29, and i have been driving harder.
The computer is notoriously wrong from some informal tests done on this forum. Mine gets ~21 on my commute. I don't spend much time on the highway, so I'd have to guess 24-25. The best mileage ever was during break-in: nearly 32 mpg on the interstate driving slower than I usually do.
My commute to work is about 25 miles one way, it's a mix of freeway and through town. I get 24-25 mpg using the old school way, miles driven divided by gallons used. I don't think that's to bad considering my window sticker said 18 city and 26 highway.
2007 59K MSCAI
25 mpg suburban
26 mpg interstate
Both figures are calculated from miles traveled and fuel consumed. I've found that the OBC mpg numbers are 4%-5% optimistic.