digidesign interface with nuendo

[krevet]

Hi, i just bought a 40 channel analog mixin desk, and need to get it connected to my DAW.
Up to now i ve been usin a focusrite saffire (8inputs) with 16 more inputs comin in through adat from an alesis 24harddiskrecorder, but its not the most pro setup imaginable. SO...

I m lookin for a decent ad/da-convertor. Im recently workin with nuendo, but wanna keep my options open to switch to PT at some point. So im considering buyin 5 digidesign-888-interfaces (the TDM series)
Can i link up to 5 of em together?
What additional hardware would i need?
And can i use it with nuendo for now?
If i switch to PT HD, would the TDM interfaces be compatible ?

Thanx

[krevet]

woops , wrong section
sorry bout that