Hi Walter,
I am in MC6 and I guess you understand that replacing Mojo DX with any of those boxes is not a proper solution in any way.
Mac only has 4 slots if you dont expand with Cubix, with a cost of a new Z800.
There is not a solution for us to work with the computer monitors.
Have anyone tested this? -
http://www.blackmagic-design.com/products/dviextender/