Evo/Lution is a live CD with a graphical installer for Arch Linux. Evo, the live CD, is an Arch based OS that cannot be installed. It is simply a platform to run the Lution installer, which is made to install Arch. It has options to install anything ranging from the Arch base, to base + the packages you select, including complete turn key desktop environments. The installer downloads all the packages you select from the Arch repositories during the install process so you always end up with a current, up to date install.