Has anyone ever tested the shelf life of normal untreated gas? I had a car sit around for about 4 years, never treated the gas. When I finally got around to starting it up, it worked just fine, ran a little rough at the beginning, but other than that I didn't have a problem. Granted, that's only one experience, and I do add Stabil now, but I'm just wondering if it's just marketing scare tactics, kinda like the expiration date on water.