Has anyone else started using this stuff exclusively? I try to be loyal to a brand, but this was pathetic. We run oxygenated gas from October to March here, got to love the state of Texas REQUIRING you put something in your car to ruin it, and then Shell came out with the nitrogen enriched gas. I've been using Shell about 75% of the time since I got the car, and nothing but Shell since probably January. In the last 12 to 15 tanks worth of Shell though, my range fell from roughly 380 miles per tank to under 310. At 380, I was just brushing against E, with the Shell now I'm about to push the car into a fill up at 300 miles. I thought maybe it could be one station, but I've filled up in Las Cruces, New Mexico and 2 different stations here in El Paso. I even switched to 86 octane at Sam's and dumped in some octane boost, and my mileage went back to normal.