Thanks for the replies:
One of my considerations for SD / CF is I'd have to run such an interface to the outside or what's the point..?
I'm thinking SD simply because it's smaller - more discrete, and the A1200 concerned is seriously running out of appropriate places to cut new holes.
Hmmm. Addonics, eh? Looks intersting...
...and that rather large PCB looks like it could stand some serious trimming courtesy of Messier Dremel.