Late 70's / early 80's Woodchuck wood furnace in the basement, looking at replacing with a shiny new more efficient one in the next year or two. It has needed the occasional new firebricks, pipe, and last year a bit of welding. After I replace it, it will be kept around for future shop heating duty (whenever I get a shop built).
Current "daily driver" saws are 2 Dolmars, a 7300 bought this spring, and a 5100 that's just a couple months old. I expect them to last 20+ years, cutting 10-20 cords a year. Of course, something newer and shinier might well replace them before that.
Until I found this site, I was cutting with a 30 year old Olympik 271, a 5 year old MS290 and a 20 year old 280E Echo top handle. No major problems with any of them, carb kit on the 271 a couple years ago, and fuel lines on the Stihl. (The 290 also had some parts replaced due to a moron tractor driver...guess who?) I've got them on standby in the shed for those days I have helpers, or if something happens to one of the Dolmars. I may be replacing the Echo in the next year, but I sure don't NEED to...Dang you ArboristSite!!!