Mine is a 4cyl. I missed the v6 by a year and I really wanted the v6 along with all the extra goodies you got. The 4cyl were de-contented somewhat; no back up camera, puddle lamps, home link system... They also took out the hill desent control.
The GV gets an indicated 18.2mpg around town most of the time. My trips are very short and if I drive more than 2 miles at a time, it always gets better. I say an indicated 18.2mpg as I have larger tires on the truck and have to add 7% to make up for the difference. It woks out to be about 19.4 mpg. When I manually figure the mileage when filling up, I notmally get about 19.2 mpg so the computer is normally off about 2-3 tenths of a mpg.
I don't drive very fast in town, only on the interstate/hwys. Around Lincoln Nebraska where I live, we don't have a lot of hills and we are only about 1200' above sea level. The conditions are right for decent gas mileage.
Going down the interstate at 65 mph without the box and roof bars on top, I see about 24mpg real numbers. All in all, it does a nice job.
I'm going to be selling it once I find a good Sami to build up or at least that is my plan. My wife may have other ideas about what we do. She should be happy though, we paid off the new Lexus she drives last year so eliminating an other car payment would sure be nice.
Rob