So after about 3 years of ownership, I finally managed to get two fill-ups back to back with an avg MPG of 29 (calculated) or 30 (MFI), at 375 miles per tank - mixed driving. Pretty stoked. On highways, i kept it at 62-65 (LOL), and everywhere else at speed limit. My last fill up was 27 mpg, w a few spirited runs, and keeping up w traffic on highways. So with the fourth tank in, i already gave up on the whole fuel economy game/efforts, and started up again w/ normal NFG throttle inputs. I will typically average about 23-24.
Today i get a nice present via text, from wifey showing me her 20 mile commute - almost all highway. After 2 good years of bitching and whining about fuel economy when on eco-tank/mode, i think it has finally paid off...lol And.. she won't tell me how fast she was moving.