Setting up a RPi could not be easier. Arch is now available in hard-float, which makes it worth using.
It's really just a matter of sudo dd bs=1m if=Image.img of=/dev/rdiskX. Once you're done, configure your unit, update and install desired packages (pacman). If you wish you can use dd again to create your own backup image to save you the hassle of re-installing packages if you mess things up!