Here in New Jersey they've added 10% ethanol to our gas and I've heard that it can cause fuel system deterioration, at least in older equipment. On the net I've seen several opinions and they range from rebuild now to, at 10% ethanol the fuel is harmless. I talked to the folks at Briggs & Stratton about some of my equipment and they said that officially they approve of ethanol but that the formulations of gasoline are changing so fast that they can't keep up and they just don't know and that I should find a source of conventional gasoline, if I can. I imagine that it's the same situation at Kawasaki, which is causing some concerns about my "Z". And aside from the engine, what about the tanks and lines - will they eventually leak and need replacement? I imagine everyone has an opinion, but what I'm looking for are actual experiences especially from individuals living in the west, where gasahol has been used for years. Any fuel system problems like corroded soft metal or swollen rubber, leaks , etc., especially in older equipment and autos, for that matter, that have had considerable exposure to ethanol? When I purchased my Hustler Z a few years ago I figured, with care, it would be the last mower I'd ever buy. Now, when you gas up it's like feeding poison to an old friend.