CrossRoads:
Hmm, yes, the quadram needs 5v to work, so maybe not a good option. Underpowering it won't damage anything, it just won't work.However, 3.3V versions of the chip are also available
http://www.mouser.com/ProductDetail/Alliance-Memory/AS7C34096A-12TIN/?qs=sGAEpiMZZMt9mBA6nIyysDfDw0vDQxSwaJg9Cfc3Tkc%3D
so the Rugged Circuits folks could change the address latch to a 3.3V part and have a Due compatible board.
Whether the part fits neatly into the Due address space is different matter. If the sketch is directly controlling the memory addressing as I outlined above, I don't think it matters.
I am comfortable working with SMD ICs (lot's of experiencing desoldering them too) so I may try getting the shield and replacing latch IC and memory with 3.3V part.