I wanted to keep my internal SSD for osx, and use an external drive (usb or thunderbolt) for windows. However I can't seem to figure out how to get bootcamp to install on the external drive. With my 2014 laptop, i could EFI boot the windows install media, but even after disabling all the secure boot options that won't seem to drop me into the install. For now I have a small windows partition on the internal drive, and keeping my data on external which works, but not idea. Really glad I ordered a custom model with a bigger drive, since bootcamping on even the stock i5 would be tight. Note: using goalque's automate-eGPU EFI to boot into installed windows so I can run eGPU with monitor hooked to mini directly.