To be honest unless there's some other major benefits apart from the colour LCD I can't really see it being worth it - you might as well just plug in a secondary monitor and use that (even something out of a skip will be bigger and higher resolution).
I use a G15rev1 (deliberately bought just as the rev2 was coming out, as I wanted the volume dial and blue backlight) and basically just use the panel to monitor my cpu/ram usage. I quite like it but don't really see the need for having a mini colour display in there.
As for the G1-18 macro keys on the left hand side, I literally haven't used them at all.