What you have done is come across a Kubota hater. There are many Kubota Haters out there and here. Kubota does not discontinue parts after 5 years. Eventually, and I am not sure what time frame that is, parts will be diffucult to buy. Strange for example that a Honda Trail 90 from 1968 I can buy just about every part needed for the engine but things like rubber parts and decals are hard to find and costly, odd though that it still runs and the Harley produced (Armechi) Baha 100 of the same era is in the trash bin 20 years ago--try to get parts for that.
You see, all products now--ALL Products---have a built in life expectancy and at some point parts will become hard to find/costly. Consider that many domestic tractors use Japanese engines, now how do you think that will work out 20 years from now.
Sooooooo, in short, you have been misguided by a classic Kubota hater. Such people hate Kubotas and usually every thing not made in America which is just about every thing nowadays. Why this is the case is a subject often debated--hotly---and never fully comprehended. Unfortunately, we like to over simplify things--we Americans--and Kubota haters see Kubota (Honda, Toyota, Sony etc etc) as easy scapegoats for a complex problem. If you like the Kubota--BUY it, if you like a similar JD, NH etc product--buy it instead--anything you buy today--MAY---have diffuculty getting SOME parts for 20 years from now. If this is not acceptable--buy a Ford 8N. Good luck. Oh, some persons think the world will end in 2013, Aztek calendar, I would not be one of them, see you on Jan 1, 2014, me and my 'bota. J