Thanks for your interest. It's the C1100 with a duplex attachment. Although the driver on the disk works fine with Vista in would not allow me duplex on 7. I tried to find an updated driver from Epson without success. Windows 7 own driver would also not allow duplex.
In the end I had to use another computer as a printer server but that's a bit OTT. Replacing the scanner (which I did) was one thing but replacing the duplex colour laser was not on.
I took 7 off and am awaiting the outcome of the real article!