Crappy gas last few years has ruined a lot of saws. Everyone knows it. I found 1 station in the county that sells gas that does not have alcohol in it but the delivery driver tells me if the station orders 7,000 gallons and the regular tank won't hold it all, they just drop the hose in the premium tank. Sweet. I've probably gone through 30 pistons and cylinders in the last 1/2 dozen years. Before that I only had to replace 1 in 30 years. Part I blame on the carbs too. A guy at the dealer told me yesterday to put Walbro carbs on my 044's to have fewer problems. I looked today and all 5 have Zama (I always thought they were crap and they keep changing the part numbers) and all my spare new ones in boxes are Zama. Any opinion? Are Zama and Walbros knock offs of each other with interechangable parts as different venders for same stihl models? He also told me he knows a guy that uses aviation fuel in his saw. Any thoughts or experience on that? Thanks guys.