People are very happy with both brands. Few are dissappointed.
It really comes down to you shopping around and sitting on the different tractors that appeal to you. Test drive whenever possible.
Some of the things you should consider is horsepower, weight of the tractor, hydro or gear transmission, features and ergonomics. For example, is the loader easily taken off the tractor or not.?? Are you good with a clutch.?? What are the tasks you will be performing...mowing or haying.?? Snowblowing.?? Moving a lot of gravel or field work.?? On and on and on....
Get serious in your mind about what sort of tasks you are going to ask of the tractor. This will point you to the size and features of the tractor that best fits you.
Oh, and don't get sucked in to thinking Kubota is 10% less than Deere. Find out for yourself. It could be the other way around. Some will say Kioti is better than Kubota and less $$$$$.
Find out for yourself....you may up buying a Mahindra.??
And, as stated above...be sure to compare tractors that are comparable. It can get confusing so take your time and study the specs. Have the dealer point out the different lines of each brand.
Lots of good tractors out there and Kubota and Deere aren't the only ones.
Best of luck in your search.