I would like to connect 6 monitors to my computer to form one large desktop.
I read that solutions by nVidia require Xinerama however they appear to be quite fiddly and may require editing xorg.conf.
AMD on the other hand have support 6 displays using one card with Eyefinity however there was a reported issue with AMD drivers not working on Ubuntu 16.04.
What is the simplest (no manual xorg.conf edits), reliable (non buggy) way to set up Ubuntu 16.04 with 6 monitors?
This is a very and dependent not only on your graphics card but also the desktop manager. If you need to use graphics cards then using gnome or KDE is not possible. With AMD on the other hand you can run 6 monitors of a single card however be prepared to pay for an additional adapter/hub.