Which linux distro is most visually pleasing UX wise. I'm looking for something with a good UX framework like material design or metro. It's for UX research.

Elementary seems pretty good

@Null-Device except that in some cases changing the de can definitely wreck yo shit man :/

As far as aesthetically pleasing distros: elementary os, ubuntu, fedora( with many different des), mageia, chskra, eXtern os, joemo ma os.

Cheers!