Plextor dissapointment

My PlexWriter 121032 reads all subchannel data, but according to the information it sends to CloneCD, the burner doesn't write PW subs. Blindwrite doesn't report any problem, although neither program can produce a perfect backup of my Diablo II Play disc. Is this truly a failing of Plextor burners or can I do something to improve its capabilites?
other notes: firmware 1.08