my dad bought a john deere in 1983. he mowed 6 acres with it weekly, including stumps and roots. it went through a tornado in 1985 and did a lot of tree hauling, pulling, and other clean up work in the following years. you'd be surprised how much needs done after a tornado. it's still going strong, although they purchased another JD at home depot for mom to use, his still did the greater part of the mowing. dad's gone now, but i still use that old deere to help mom mow when i can and if her brother isn't using it.
the only things replaced on it were the seat which had gotten a few tears in the twister, a couple of front tires and belts for the mower deck. i've gotta say though, the quality between the newer one and the older one are worlds apart, but then again, the new one cost about half as much as the old one.