I'll toss in amother vote for the Deere 310c or 410c.
A friend has a 310c 4x4 turbo, 89 vintage, currently pushing 8000hrs. He's the second owner, I'm also friends with the original owner and have ran the machine since new.
It's had some major work done to it (trans & rearend) but it's all been because of operator error and abuse, not poor design. The rear valves need a rebuild and the cab floor is due to be replaced. Bucket linkage is due for pins and bushings. The extendable dipper is overdue for a rebuild also.
This machine has spent most of it's life doing septic fields, shes carried a 36" bucket on the hoe most often. It was also eqipped since new with oversize rubber from a 510 machine, it floats pretty good on soft ground and sand.
The worst I can say about it is cold weather starting, in single digit temps, not gonna happen without heat.
You do need to look out for the machine going into 4x4 by mistake, Deere put a handle through the floor to engage & disengage. Down is 4x4, it's easy to hit the handle with your foot and lock it in by accident, not good when roading the machine on asphalt. Easily solved by putting a block of wood under the handle to hold it up.
Ed