If the YM2000 is of the correct size, weight, and power for the jobs you need to do, it's a great machine for you. The engine is powerful and very user friendly, the transmission and rear end ought to have essentially an infinite service life if kept lubed and clean.
I don't know what you mean by "toughness." I have literally broken an anvil before. Abuse will ruin anything. Anything. If you're planning to abuse it, it won't last. Neither will the KuboDeereHollindra any new dealer would sell you. If you're going to chain the loader to a tree stump and back up, pulling it tight, then repeatedly drop the clutch at full throttle, something will break. Maybe the chain, maybe the loader, maybe the tree, maybe the front driveshaft or gears. 8th gear blasts at full speed into ditches or rocks will break or bend steering gear, spindles, or what have you. If you're not going to abuse it, I don't know what you're really asking about.
These things are simple to work on, and extremely well built. They lack many of the features seen on newer machines. For me, that's a benefit, because there is very little to go wrong. The YM2000 and it's American sibling, the YM240, are less refined than new machines. The big 2 cylinder is loud and clanky sounding. It also has a superb powerband for tractor-type work. I love it. These are simple, effective tools. The word simple keeps coming up. There's a standard response for all the posters who can't make their machine, especially these big 2 cylinders, run. I was told myself:
Make sure there is decent fuel.
Clean/check the fuel filter.
Bleed the system by loosening three bolts in order.
Connect good battery/battery booster after cleaning all terminals/connections.
Crank as instructed in the manual.
Barring extraordinary cases of abuse/neglect, or errors in re-assembly, this virtually always resurrects the tractor.
Having said that, any of the other Japanese brands also make excellent quality little tractors too. They are all superb. The biggest advantage is that Yanmar has an extensive parts supply and a large presence on any internet tractor forum you visit. Kubota has reasonably good parts availability too. The others, like Iseki, Mitsubishi, Shibaura and Hinomoto are less common, and hard parts will be trickier to find. Consumables like filters are auto parts store items for any of the them. However, they are all very well built, excellent quality machines that should last thousands of hours. I am not scared of them, per se.
Yanmars have an extensive series of what I'll euphemistically call "sales locations," who sell what are called "reconditioned" tractors. There has been a vast range of experiences buying these machines, from nightmare to fabulous. Be on guard, and ask questions about it, if the tractor doesn't look like it is 30 years old.
Things like "rebuilt top to bottom" or "new engine parts" and similar are often indicators of a reconditioned tractor. If it's from a place that claims to be a dealer, ask what parts he keeps in stock. He will almost certainly claim that he "can get whatever you need." That's true, and dandy, but you can as well. A place that doesn't stock parts for you won't be of any help if you have trouble. He's probably ordering from one of the advertisers here, anyway.
I mention the reconditioned situation because it sounds as if you're looking at a particular machine, not generally. Just be on guard for tractors that look brand new. If it looks new, something has been done to the tractor. Ask where, why, and by whom. See if what they tell you makes sense.
Good luck in your search. Let us know what you buy.
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