Both my Escom made A1200s seem to work fine with all the expansion
cards I've ever plugged in to them
.
My advice would be to try and store the boards you don't use, if you
have the space.
If you do get rid of any Escom boards in favour of the C= boards make
sure the C= boards have 3.1 roms fitted, otherwise swap them over from
the Escom boards.
But like I said my Escom boards have thus far been fine.