The Mitsubishi was a very good eng. The two tractors are the same otherwise, except the 264 has linked hst pedals.
Most problems I have seen, with any tractor, any brand could have been avoided with a propper Pre delivery inspection (PDI) and follow up inspection after initial use, and a complete 50 hr service.
A dealer is charged for assemble and a PDI from the manufacture. Our dealership Rechecks every thing that was assembled and another PDI.
This is to avoid the problems. A broken lock washer when installing the loader at the assembly center in 20 Hrs will loosen on the loader,A battery not properly installed on a tractor will shake loose the first time out, the list can go on and on.
So to answer your question of problem areas, it all depends
If set up correctly, its a good little tractor for the money.
I would check all fasteners, hose and wire routing, fluids etc. This is something all manufactures recommend in the operator manual that the owner do with in the first 8 hrs.and in the service table as a Daily check
As for the parts TYM has a good stock, check with your local (selling) dealer