yo yo yo! You'll love it.
I'm running a Matrix Orbital MX421 (the 4 line)
You would not believe the stuff this puppy can display
Some samples of the "Virtual display" are here.
http://www.uploadit.org/gallery/13039
I have it set up to go through like 25 screens so if you need a config file for a 4 line display I got your back. It may be easier to delete the ones you don't want than to config it yourself. (unless you are a nerd of course)
It runs on the MO display as well as your desktop if you want. Max nerdiness
You can still download a 30 day trial and just run it on your desktop if you wish for testing purposes. PM me with your email address. Phone too if in US or Canada. I can send you the file and you can play before you pay.
The LCDC software is $9.95 alone or with a standard display but IS included on the MX models. (go for the 4 line if you got the space.)
some pics in the Wavemaster as well
http://www.uploadit.org/gallery/13844
Oh yeah, I do have it dialed into MBM5