I've got a 12 year old lawn machines Home Depot special that has run like a top for most of its life. Occasional oil changes and a carb cleaning is all it's ever asked for. Ran on regular gas too and I never worried one bit if the gas was old or not. Probably even has the original spark plug. Briggs engine, no plastic parts where there should be metal.
I also have a 6 year old Toro 22inch recycler self-propelled mower that's been nothing but an unforgiving bitch goddess since I brought it home. Seized up in the first season due to oil consumption, has had a broken starter cable, and off and on trouble with the self-propelled mechanism. I'm handy enough to handle the problems myself, but my god, a mower shouldn't need this much TLC.
This year, I'm giving these guys a shot: Robin Autopilot . They'll set me up in a couple of weeks and we'll see how it goes. I'm on a half acre lot with a big dog and some and some 15 - 20degree inclines, so that little mowers gonna have its work cut out for it.