Not familiar w/ kubota MMM. But I have a 72" for my ford. If MMM does NOT have 4" or wider pneumatic tires, it will rut the lawn during spring rains w/ narrow hard rubber or plastic wheels.
If you find a reasonable used mower, in good condition, so be it. But there is a decline in mid-mounts and 3 point mowers. They are - S L O W- and lack maneuverability.
The zero turn is only way to go. You are NOT mowing huge acreage, so your time saving won't be as great.
Just so you can avoid the proverbial self kick in the pants, try to demo a zero turn before spending 3 or 4 thousand on a mid-mount attachment. If you perform any woods work, the mmm loves to get hung up on grade changes do to minimal ground clearance. Zero turns have decreased in cost, residential models.
EDIT: Flail mowers consume significant HP. True? Rear finish mowers require constant turning to observe mower while avoiding a collision, True?
