I have an AD16X + DA16X combo connected to older PCI cards in a Magma 4 slot chassis (HD4)
This setup has worked fine with: G5 with PCI Magma card and 10.5, Harpertown Mac Pro with PCIe Magma card and 10.6, Hackintosh i5 with PCIe Magma card and 10.7 and a MacBook Pro 5,2 with Expresscard 34 Magma card and 10.7.
I used the PCIe computers with PT9HD at first and have now upgraded to PT10HD without incident (actually, everything seems slicker on PT10- very happy)
Apogee never approved the use of their convertors (with HD interface cards) for use with expansion chassis. I think this is because very, very occasionally the interfaces are not recognised by ProTools. Cancelling the ProTools launch, power cycling the convertors and re-launching ProTools always fixes it.
This is the only issue I've ever had and it happens so infrequently I've never worried about it.
Unfortunately, I can't vouch for a new MacPro and 10.8, as I took one look at the MacPro prices
and built a Hackintosh
