I got about 23-25mpg on an 1800 mile round trip and I usually get about 275 miles before I fill up and I usually have just a tad under 1/8th of a tank left.
Best of all...I'm running 4.10's :nice: I've also got an O/R H, CAI w/ a K&N, ported and polished upper plenum, flows (which I hate).