The only 21" LCD I've tried is the samsung 21.3" one and while the picture is good the lag is horrible. I think there is a Dell one of a similar size which OND is using in his futuristic cab which may be better in that regard.
If you go to 19 or 20" there are more options but other peeps here can probably give you advice on the best ones out there.
The thing is - peeps seem to be more against the positioning of the monitor than the actual monitor itself as it looks a bit high where it is.
Have a look at the MVC 2.0 cab if you want to see the benefit of a large monitor in vertical mode.
I think your Goonies cab rocks though. The artwork is some of the best I've seen and really suits it. This is one of the cabs that I've been following from the start and it looks pretty sweet
