I am always open minded with other brands and I love to discover a truly good value with a new brand. But over and over with tractors at least, other brands make me appreciate my Kubotas more. Sometimes it's little stuff that you wouldn't always think about up front, or stuff that doesn't translate to paper. Sometimes its stuff you only discover after using the tractor for a while. So while I am open minded, I sort of keep proving to myself that if I don't want surprises and I want to be able to take things for granted, then stick with Kubota. In my mind they are like the Honda of the tractor world. Maybe more expensive and certainly not perfect, but they do their homework, they build a good product (with control over almost all the components from engine to HST to chassis to loader, unlike almost every other brand), and it's a known quantity for me. They also stand behind their products which can be an issue with other brands.
I remember when my neighbor got his Mahindra, I looked it over and thought, nice tractor. Then I noticed no suspension on the seat. Then I noticed the loader valves were real abrupt feeling with none of the finesse or fine control I was used to in my Kubota. Then I noticed that his loader rating, which was higher than mine despite his tractor being one size down, wasn't worth the paper it was printed on because the smaller tractor was simply not stable with heavy loads, and the loader itself had a real limited reach and height. Finally, he's had several warranty issues and they have all been a struggle (one of his Mahindras has sat at a dealer for months while they are in a game of finger-pointing with corporate). I had a similar experience with a Deere E model and an LS. On first glance they all looked good to me but it wasn't until some time in the seat that I started noticing some sore spots.
I think all the brands are quite good overall, especially if you can ferret out who makes the tractor and components that go into the other brands that don't cover the "soup to nuts" process Kubota has, and can ensure you are making a good choice. And all of the brands will get the job done, no question about it. Rural King seems like the one to beat right now, if you want one of the second tier brands at a bargain price.
Kubotas are going to be more expensive, but I feel like they have earned their reputation and there is a reason they have 50% of the market for compact tractors despite being more expensive. Whether or not that is a factor depends on the buyer and what's important to the buyer. If price is the only true reason someone passes on Kubota (I've said many times that loader specs are not a real reason**) then it's important to make sure the cost savings justify going with one of the other brands. Based on what I have seen with some of the other competing tractors I have run, the cost savings wouldn't make up for the annoyance with some of the factors I mentioned above.
** Also compare tractor weight of course. Sometimes Kubotas are lighter tractors and the loader capacity goes hand in hand with that. If you are after the heaviest baddest tractor out there with the stoutest loader, it's probably not going to be a Kubota, or at least not a B or L model (look at MX, etc).