The issues I've had with it over its lifetime are:

1) Leaked oil from the head gasket after several years. After changing to a better quality oil, it stopped leaking and has not been an issue since.

2) The mower deck has finally started to show some signs of rust within the past 1-2 years. If it fell apart tomorrow, it wouldn't owe me anything.

3) Last fall the original pullstring broke. A new assembly cost about $25 shipped and required 3 screws to replace.

4) Several years ago, the handle on one of the blade height adjustments snapped off. I still have the handle and have been meaning to try to weld it back on, but I've made do by simply stomping on this wheel or picking up the mower and slamming it back down.

Other than that, it starts on the first pull virtually every single time, regardless of how long it's sat (thanks to Honda's automatic choke system, per Edge's post from earlier this week). It's drank ethanol fuel for its entire life until recently when I finally found ethanol-free gas near me. I've probably only changed the oil 5 times over the course of its life (not really proud of that lack of routine maintenance), but it continues to run.

As Edge said, I don't think you can go wrong with a mower that has a Honda engine. They seem to take plenty of abuse.