Runcores are Chinese, as is your whole mini for that matter, the Runcores are just of a very high quality.
I have a SuperTalent, bought it from Newegg when the mini 9's first came out, they have continually improved as they have released subsequent models.
Why buy the OS? Because it's the right thing to do, it's less than $30, and on this forum it is the way we work.
Why steal an OS, if you want a free OS install a version of Linux. I have, and I can tell you it is worth buying the Mac OS just from ease of installation and the fact that when you are finished, if you do it properly, everything that should work does.