I'm going to answer this from a different perspective. I have never personally owned any tractors, but I have worked on all of the big three in the CUT market. I worked 6 years as a mechanic at an exclusively Kubota dealer, I worked another 6 at at dealer that sold Kubota and New Holland, I spent 2+ years as an independent working on all types of equipment, and I spent 8 years working for a Landscape Contractor that owned a variety of equipment, Kubota, New Holland, Ditch Witch, Bobcat, and Case.
I recommend Kubota because they hands down have the best small diesel engine in the world. There is a reason almost every OEM that uses a diesel engine offers Kubota engines. Their tractor design is simple. they use the most straight forward approach. New Holland and John Deere are far more complicated than they need to be to accomplish the same thing. The analogy I use most, for those that are familiar with handguns. Kubota is like the Glock of tractors, they use the fewest parts and simplest design to achieve the goal. I have seen 2 Kubota engine failures in 23 years that were not operator induced. One was an L-series that had a bad intake gasket from the factory, and the other was a spun rod bearing that could not be determined whose fault it was and Kubota took care of.
I also agree with the point that was made about Kubota being made by Kubota, Not a John Deere being made by Yanmar (which in my opinion is the noisiest & sloppiest built of the big 3 engines), or a New Holland made by Iseka or whatever European company owns them this week.
I also believe that Kubota has the best parts network of the three. Try getting a backordered part from John Deere or New Holland in 3 days from Japan. I can get a part from Japan faster than I can get a part from Texas UPS ground and for about the same cost as next day air from the East coast.
One more point, of the 3, Kubota in my experience is cheapest to repair.
Brian