Hi Mark,
Nice cabinet! I now wish I had stuck to my original bartop plans...
Regarding your chosen monitor (Toshiba 21" 21N21B TV) and the Arcade VGA card...I was lead to believe that the SCART socket on that model of TV was not RGB, and the picture quality was not as good as you would get from a true RGB SCART TV (this was from a guy on the old Ultimarc forums...)
Obviously, you are very happy with the picture quality...any chances of putting up a few pictures of games running on the TV? If they look good, that would save me redesigning my cabinet plans...