I’m a Mac Mini user for about ten years now, I’m on my third one during that time ..
I sold the others on ebay when I upgraded, they were still working fine. The one I
have now is a 2012 model with the Yosemite OS.
I do automatic back ups with Time Machine with a external hard drive. I recently
bought a Mac Book Pro and connected the external hard drive to it and all my files,
music, internet data, etc, transferred perfectly.. You can’t go wrong with a Mac Mini.