-does work, but I haven't been able to make it print duplex on cards, especially when generating
-front and back pages separatly.
+but I haven't been able to make it print on both sides of cards,
+partly because using dumplex option in cups seems to segfault GhostScript
+and/or C<rastertoevolis> cups filter depending on combination of duplex
+options.
+
+I also needed pixel perfect transfer to printer, and cups
+bitmap format is always in color, leaving final pixel modifications down
+to cups filter which always produced differences between file sent to
+printer and perfect black and white rendition of it.