I have a LITE-ON LTR-40125S @ 48125S (a CD burner).
The drive LITE-ON LTR-40125S with firmware ZS0R was flashed to LTR-48125S with firware 1S07.
The EEPROM utility by codeguys returns checksum invalid for my drive (and also refuses to repair checksum) .
Using the EEPROM utility to read the EEPROM and then using a hex or text editor reveals (when using a text or hex editor) text strings “LTR-40125S” in EEPROM and no text string of refering to LTR-48125S.
Does a problem with my EEPROM exist?
The LTR-40125s can converted to LTR-48125[U]W[/U].
Is there a benefit to crossflashing to the “W” drive over the “S”?
w and s share the same hardware, there’s only the benefit of newer firmware, but i have no idea which one is newer (VS0D or 1S07).
the text in the eeprom doesn’t matter. if the drive woks fine, don’t mess with it.
I Believe 1S07 is newer.
Would there be a benefit to acquiring and flashing 48125S EEPROM?
No, it would probably kill your drive. Each EEPROM contains specific factory calibration data for each drive. So flashing to another drives EEPROM in most cases will cause poor burning quality. It’s best not to play with the EEPROM. Just keep a backup for emergencies and only write this backup to the drive if all else fails. 
I shall leave emy EEPROM how it is then.
Thanks to those who participated in this thread, excluding myself.