[Rimrock]

It's actually quite simple; there is no free lunch. Or let me put it this way; driving down the highway on the rims, with no tires on your pickup truck to save money, may take you some miles, birds are singing and life feels good....
Hydraulics made by non professional machine shops ; 'just rims, no tires'. Cheap.
Hydraulics made by professional hydraulic machine shops; 'rim + tires'. Less cheap.
A often used option; by a cheap entry level machine, rip out the original pump and valve block as quick as possible, install the real deal from a high end supplier. Still got a reasonable priced machine, but now it WORKS. It's always a joy when stuff works as intended.