You have a good point re needing a working tractor. However on the GP's "just by it from AliBaba" I'd really be surprised if such items would last long enough to become the "rusted one in a field" at a later date; I'd expect the "expensive" home made one might be that long lasting though.
It depends on the item. China is known for low quality goods because companies outsource to China to save money. They are telling the companies in China to make cheap crap. The manufacturers are perfectly capable and more than happy to make high quality items, it just isn't requested of them very often. It is always "use the thinnest possible" not "make it twice as thick as it really needs to be".
