I voted for the Metro interface because I'm currently using Win 8 on a touch enabled laptop. Though, I am still using ViStart on my testing rig running CP. I saw no point in paying for the Start8 if this does pretty much the same thing.
Don't mind me asking, but what are you using the six monitors for? I thought that having a 3xdisplay was cool but this is off the charts, in a good way.