All too true. Both my work and home computers run Arch. At work, dual monitors on a single ati video card with xinerama was a HUGE pain in the ass. I ended up just running without xinerama and the Driver/Screen/Monitor/Server sections, let X choose its defaults, and then use xrandr to get the monitors working proper, although they still don't share the same background image, I can live with it.

In Archs defense though, setting up xorg is simply installing the packages which is trivially easy with pacman. I love it to death.