emusonacid! legacy

Just getting around to using the digital i/os finally on my 1820m. I emailed EMU with some questions and they were completely useless so...

Basically I was told I can't use more than one 1820m/1616m on the same system. Sucks wanted to get more i/os. So finally thinking about getting another interface with AES/EBU to send to th digital ins/outs and coax i/o.

Does anyone know if I can use these in addition to the analog i/os or will these take cut down the amount of analog i/os (like how the RCA in shares ins 1 & 2)?

Was basically looking at somekind of somewhat decent DAC box like Edirol, M-Audio etc.. with external power supply and use their AES/EBU or coax to add more ins, will this work or cut down on th analog i/o count on the 1820m? I realize I could just install that at the same time but it would be easier to manage everything through patchmix since I'm familiar with it and like its' routing.