I have a feeling the answer would be, not amazingly well!
I have recceomended to people to use smaller maps, either 64x64 or 128x128 and to disable Full Detail and Full Animation. I have some save games I can load up and see how it copes. But I have seen x86 pcs crawl with some games I've done.
But I will try and see how far I can push it before it becomes unplayable.