I can't give ya great advice, but if determined to buy, and do this job, as others have said, buy big, knock the job out, then sell and buy what you need for next place and your specific tasks. If you buy small, it will take a long time, be wore out, and cause you anguish in repairs as you try to farm your new place. If you buy big, for the job, and keep it, your operating expenses for your new farm will be too high. Think of fuel prices, hydraulic fluid prices, oil, tires, bearings, etc--the bigger they are, the more expensive to fix.
If set on buying, again, buy for that job, then sell and buy suitable tractor for next job. If you can, shoot, keep both.
Tractors like company, and you can split the chores between the two. As far as brand name opinion, buying the right size for the job is it, all the brand names you mentioned will all do you good. Find out what dealer has a good reputation in your area, treats folks right, and go with that brand.
They will all get the work done, just a matter of how you want to go about it, and how much money you have.
Again, I would urge you to find out which dealers/independent shops are friendly, fair, and good in your area...then buy something common with plenty of parts availability, unless you don't mind down time. Find out what shops good, if you don't know anybody, look at what the bulk of brand names are around you, then that shop/dealer is probably good.
I'm sure this don't help, its probably what your wondering about, so your not alone.
I am but an ignorant fool, in this world to learn.
Take care