Thanks for reposting the stamps I asked for.
You mentioned a possible "medium" perf hole size for the Ashton-Potter.
Below are the APCL blocks from my earlier post along with a matching CBN single at left (I can't find the CBN plate blocks and fear that they got lost in a move).
First the APCL 1365i large holes matched to CBN 1365 large holes. I don't really see a difference.
Next the APCL 1373ii large holes matched to CBN 1373 large holes. Again, I don't see a difference.
Finally, the APCL 1369i small holes matched to CBN 1369 large holes. The difference is obvious.