I agree that we have not been given enough info on what each tractor comes with, but in general, I would go for the Kubota if it is a new one, and is equipped similarly to the NH.
855 hours in 5 years is a good bit above what the "average" homeowner would put on a compact tractor per year according to what I've read on this forum. You have no idea how well it has been maintained, what problems it has had. For that money, or a little more, there are plenty of new tractors out there that can be financed, and then you would know how it has been maintained.
As for the size, property size alone does not dictate that you need that much tractor. I maintain a total of 11 acres of my own, plus do work on other properties with only a 21HP tractor with no problem. My cousin has a NH TC33 gear model for 22+ acres that he mows, gardens, etc. with no problems. The Kubota L2800 or similar from another brand may be all you need.
John
