Welcome to TBN:thumbsup:
A question re warranty is really a question re reliability.
Suggest you use TBN as a data mine to build your personal opinion of reliability via brand.
For a particular brand's OWNING/OPERATING forum, look at least at the first 200 posts. Count how many are about "mechanical problems" versus how many are about "whee, here's what I'm doing/want to do with my tractor".
Go to the next brand, do the same.
Do this for each brand you are interested in. A pattern may start to form on paper and in your mind about kinds of problems that develop and how they are handled by real users doing real work.
Whatever you learn from this exercise, it will take maybe 15 minutes and be a far better information sample than any single reply from any particular TBN poster.
Now, this knowledge can factor into all the other decisions you have to make regarding a purchase...$$, attachments, features, dealer proximity, dealer quality, etc.
While not a strictly scientific sample technique, this approach will give you the aggregated experience of a large number of TBN members quickly... priceless:thumbsup: