If it were me I would take all the non hydro machines off the list, non hydros aren't as quick/well suited doing utility loader work. Then any non JD or Kubota, lose the possible parts issues. But that's what I would do.
Thanks! I'll definitely keep that in mind. The Yanmar YM1610D has as good a parts support as any grey market machine can, but it is older--built from 78-81. It also has a shuttle trans that allows shift on the fly, which is better than a manual tranny. There's one only an hour away, so I will go take a look at it as it will give me an idea of how the similar sized JDs will handle.
I would prefer hydrostatic, and definitely power steering, after having to horse the Bolens steering wheel around for several hours last week...