So you would be ok with the statement if he prefaced with "In my opinion" or "In my humble opinion"....because these statements are always an opinion. And by the way, Kubota does make the best tractor under 50 HP! Oops, IMHO that is! My best advise, the weekend is almost here....lighten up!!!
I don't have any problems with anybody saying anything based on opinion, just as long as they don't expect it to be perceived as fact.
The problem that we all went into when we say something is the best, especially with tractors, is that there are just too many categories that could be used for that determination. I'll pick a few examples just for the sake of conversation. Dealer network, warranty, loader lift capacity, lift height, breakout force, ground speed, 3 Point lift, turning radius, operator station visibility, etc.
What would be more appropriate would be to pick one of those categories and say something like, for example, Kubota makes the best tractor for hydrostatic operation, because the HST Plus offers such a wide range of operational capabilities. Or you could see, Mahindra offers the best compact loader tractor because the ML156 loader is rated with the highest lift capacity, breakout force, and lift height. Or you could say, the Kioti NX series is the best compact CAB tractor because it offers dimensionally the largest cab in the segment ( I'm not sure if that's true, but the cab is huge!). Or you could say, LS makes the best compact tractors for affordability, because they offer the biggest bang for your buck in the segment.
The point is, none of these machines is the overall best. Furthermore, we all have our own opinions of what categories are more important than others, so one man's best might be a moot point or another.
Someone saying that one tractor brand is more reliable than another is something that is practically impossible to quantify. There is no way that we could get any data that would support a statement like that. For example, we all have our own personal experiences, but they might not match up with each others experiences.