The Bluestar Linux is an open source Linux distribution based on Arch Linux that uses KDE as its default desktop (and more).
Bluestar Linux is a fairly fast distribution optimized for very good performance and includes always up-to-date applications and many different desktop environments and multimedia. It comes on live DVDs which makes installation quite easy.
Today, the project developers announced Bluestar Linux Developer Edition (Plasma5) and are already available for download.
This version is not for beginners.
https://sourceforge.net/projects/bluestarlinux/files/distro/bluestar-linux-developer/