I have been working on heavy equipment for more than 40 years. I do not work on many farm tractors, but I would not own a hydrostatic machine.

A stopped up suction screen, too heavy an oil in extreme cold weather, low oil level, burst hose and trying to move machine to a better place to work on it letting air into the system, and a piece of lint, small particle of dirt will stick a piston in the hydro and grind up the hydro before you can stop the machine. Contaminating the whole system. The parts are expensive!
Customer had a John Deer 700 dozier he bought at auction for a good price. It would not back off low boy. I checked pressures and cut open charge filter. I found fine metal in filter. $46,000 later it was all good again.

Hydrostatic machines are nice to run but in my opinion they are to expensive to run for the average owner.