OK, here goes...The 455 Rancher we have does have Auto Tune. We are using the fancy pre-mixed fuel, and following the starting procedures. The saw may start up easily, or may take several pulls. Once it's running, we are told by the dealer to run it at high RPM's for 2-3 minutes. HA...problem is, as soon as we touch the throttle, it dies. Will not run. Start up again, and it does the same thing, over and over. This is at 9000' and above. Take it to the shop, which is at around 6900', and it runs fine. We precisely explain the problem to them, and leave it there. We go pick it up, and are told "just run it". Well, OK. Except when we get back in the woods, the same exact thing happens. Back to dealer...they say they will run a couple tankfuls of gas through it. We pick it up and go to the woods again, and same exact thing happens. Back to the dealer...this happened like 5 times. All they tell us is "just run it"; they have never given any better advice. Last time we picked it up, before going to the woods, we used it at home (6800') for around 1/2 hour, then shut it off for around 20 minutes. After that, it absolutely positively would not start back up. Back to the dealer....Each time they keep it for several weeks or a month, and when we pick it up all they say is....you guessed it, "Just run it". So not only is it aggravating to have the saw not work, but it is aggravating that the dealer keeps it for weeks at a time, then all they do is tell us what good saws they are. They have never told us what the problem is, or what we might do to correct it...all they say is, ....(I'm not going to say it again). We are pretty sick of that dealer. In contrast, when we took our tired old (20 years) Stihl to a different dealer; they fixed it up in one week, and it runs like a top, at all altitudes. We are not mechanics (I dearly wish I was; trying to work on the dirt bikes, learning little by little) and thought by buying a new saw we would have something that would work without having to fool around with it. We've been cutting firewood for the last 17 years, all with the Stihl. When we were shopping for the new saw at the dealer (which has both Husqvarna and Stihl), the 455 was "on sale", and we thought the Auto Tune sounded pretty good.......