I posted here before that my 810A stops ejecting frequently. Well, i finally convinced Sony Support for an RMA and today i received the replacement and wow! they sent me the latest model instead. So, for $ 6 and change to ship my old drive to Sony, i got a new DRU-820A in return… Thanks Sony!
The 810 (rebadged Benq 1640) is the better drive. The 820 is a rebadged Benq 1670 using a Panasonic chipset, does not have the scaning and solid burn features. Write quality is worse. Check the reviews.
The 820 has a Pana chipset, as ala already said. It’s the same one that also is in the Plex 750 and Pana SW-9585c drives.
The drive has issues with -R DL and +RW media as of yet.