Just to take the thread in a different direction...
Since I have been using the D9100 in my cabinet I have found that I am actually playing the games a little better. On past projects I had gone the 27" route thinking that bigger was better, but perhaps that isn't always the case especially if you are a "classics" fan. I'm starting to think that having the smaller 19" monitor helps keep you more focused on the game.
Take Robotron, for example. So much action is happening on the screen, and it just seems easier to keep focused when it is all right in front of you without having to rely so much on peripheral vision. My Robotron scores have steadily increased since I have gone from a 27" to a 19" monitor.
But playing MvsC on a 19" can't compare to a 27", so I guess it mostly depends on what kind of games you play more often. Another bonus to a 27" is that vertical games are very close their original 19" size, too. However, even that said, since I have been play testing my cab for the last couple of weeks, I'm sure I will stay with the D9100 in my cabinet now instead of switching it out later as I had originally intended.