How will this compare with the DKB 2632 add on 112mb ram card?
That's still to be determined. As far as I understand, it is *supposed* to include a maprom feature (if possible) and it is supposed to link in the memory by an autoconfig emulation, and in worst case, to include parts of the memory as (fast) ranger memory in the 0x00c0 area, but as the board is currently under development, it remains open for now.
That makes it more useful than the DKB extension which you had to link into the memory pool manually, and given that it uses more modern RAM chips, it also seems likely that it might have potentially less wait states than the original DKB extension based on old technology.