I use UX305 with Arch as my "procrastinate, err code, in coffeeshop" machine and it is a great notebook for the money. The keyboard with no backlight is main issue (for me). And the sound sucks.
I wonder if the bios is locked to prevent installing Linux.
Seems unlikely. Can't see how that would be possible without creating a support nightmare even just updating Windows with special restrictions.
Ubuntu 15.04 ins some daily build version installed without any bios changes (everything, I have tried worked like a charm).
Arch needed to disable secure boot (that should work in any Win8 labeled machine). Some things (GPU sleep) needed a bit of thinkering.