It works very well. I have a Clover Hackintosh (not OpenCore) on my [edit: cheap pre-built generic] desktop (i5-7400, iGPU, macOS has its own SSD). It works great, even allowing me to upgrade from Mojave to Catalina and forget that it's not a real Mac. My monitor always looked pink, but if I change my monitor's input color format to YPbPr it works fine. The patch that I used to fix that in Mojave is broken in Catalina, but I don't really care.

Aside from that, it works just like a real Mac in basically every way.