I see a lot of Kubotas but have never owned one. Most of the people I talk to that are running them chose them because of price and seem happy with them.
Orange, red, green, blue - I'm not sure there's a lot of difference anymore as long as you're not buying the economy models within a brand. Find a dealer around you that everybody recommends, meet him to be sure you like him and his parts/service department, then buy what he sells.