As far as the OP's original question,, Gravely riders made BIG advances as the machines get newer.
An 800 will work, but, the Pro series is so far advanced, I would never consider owning anything older as an actual tool.
As a collector item, the older ones are like a narrow frame Cub Cadet, they work, but not as good as a wide frame.
Get the newest machine you can afford, they can be pricey,,,,,,,
A 20-G with hydraulic lift is a dream to drive,,, the 24-G was the only rear engine rider with power steering,,,
Power steering is truly a lazy operators feature, heck, the engine is in the back!!
