FOR SALE. CHEAP. Under 8 hours run time.
I've used Stihl string trimmers for years, and have always liked them. So, because the Stihl dealer in Boulder is close and convenient, I went with the Stihl Wood Boss MS251. Big mistake.
It has what I consider a serious design flaw... there is only one nut holding on the bar and chain. In the photo, the other hole by the one stud and nut is just the chain tensioner screw. If the one nut holding the bar on loosens even a little bit (and it does, because it's metal studs pressed into plastic on both sides), the bar and chain fold up onto your arms with the saw running and chain spinning. Dangerous and terrifying.
It's also very hard to start at high altitude without flooding it. If you miss the first burp, you are doomed to using twist ties to hold in the handle and trigger safeties and pulling 10-20 times no choke to clear it (with a cloud of smoke), or pulling the plug, leaving the saw upside down for an hour, pulling a few times and clearing it that way.
My new saw! Husqvarna 455 Rancher. Only $100 more than the Stihl.
Heavier, but heavier duty too, and has purge bulb and compression release for easy starting. We loves it!