I have been happily running Debian (with xmonad) on a 13 inch Macbook with 16GB of memory and the retina display for almost five years now. The screen works great and I have had great success plugging into multiple external monitors including a recently purchased 3840x2160 monitor.
I think it might still dual boot into MacOS, but I don't think I have tested that for four years . . .
I think it might still dual boot into MacOS, but I don't think I have tested that for four years . . .