@chauncey
No, the Zen streamers can only rip regular CD’s. My source is 100% streaming, so this was not an issue for me.
I can’t comment on what’s under the hood of the Mk3 vs. the m2 Mac mini, and have not heard the Mac mini. You have a good question and I can only answer generally that the Mk3 is built, engineered, and optimized for one purpose only: to stream music. My experience is that in most cases, high end audio gear produces better results than electronics manufactured to serve many functions and uses. I suspect you would hear the difference, but again, that’s only an opinion.