I get around 350-375 on mixed city/highway driving. I've yet to take a 'trip' with my Accord. I almost got 400 before I put in my intake and header, but that may be just because I've got a heavier foot than when I first got her.
I only buy gas at two places, or at least I try my DAMNEST because I've found otherwise I only get about 300-325 which makes me