The service dept in any car, tractor, or machinery dealer hates warranty work. They lose money on it versus paying customers because warranty has low labor rates that don't include many things they still have to do. This is even worse if you're complaining about something not broken, but 'i hear a noise' and etc. This is another reason to not buy extended warranty and instead just pay a dealer for work done. As soon as service dept knows you're a paying customer (not just wanting a freebie), they'll love you.
If you bought the tractor at that dealer, they'll feel more obligated on your warranty work due to pressure from the sales guy who sold it. Likewise, if you bought your tractor from some other dealer and bring it into your local dealer for warranty work, while they are obligated to do it, they don't want to.
That said, so far I haven't a had a significant problem with my Kubota's to require bringing into a dealer. They just work...any defects should be discovered before you accept delivery IMO, otherwise you'll be in a sticky situation. There are electronics, but tractors are mostly mechanical components which are reliable. A tractor with a blown transmission or engine is a very rare thing. In my area you see John Deere tractors lined up at dealer service depts (it's weeks before they can have a chance to work on my mower when I acquired), but kubota dealers don't have much...they're more busy putting together new tractors than fixing old ones. You're more likely to break something due to operator error or unpredictable accident than the thing just breaking by itself.
I do the maintenance myself. Unless you're an older person and/or with disabilities, you are capable of it as these tractors are designed to be easy maintenance. This will save you lots of money too...for example, my L47 would cost ~$850 to do the 50 hr service at a dealer...I bought the parts for ~$250 (at the local dealer, where they are much cheaper than online). I already have the tools, but that can be expensive if you don't, but still ~$600 saved goes a long way. By the time you load up the tractor on a trailer (assuming you got one), drop off, wait, pick, and unload etc you could have just done it yourself. To be fair on how much the dealer charges, it did take me a good 4-5 hours to do everything (an all day event for me since I started mid day), though that will go quicker the next time around because there will be less to do per service and I've done it before.