It IS the Thinc control. Windows XP based, but windows drops into the background once it's up and running. Slower boot time due to windows of course. Should have USB ports as well as Ethernet connection. RS232 is an option as well.
These have internal hard drives and have about 4GB storage space for you to use, (if I remember right) so depends on your idea of "large".
The 200 even has a UPS built in so you don't have to worry about windows losing power and shutting down improperly. You can kill the control and the main circuit breaker and walk back to the control and watch it finish powering off...kinda strange, but vital with windows!
Don't think that since it's windows that you should try to do the standard updates etc. though, you'll get into trouble fast. Like most windows systems, if it ain't broke, don't fix it. That being said, you can add items to your system to make it more useful such as XLviewers, and even CAD/CAM if you like. Take a look at Okuma's Partners in Thinc website to see some of the things they are up to.
Partners in THINC