Just to confirm, for those wondering:
I just bought a Plextor PX-608AL, and based on advice from people here and on the rpc1 forums, I went ahead and flashed it with The Dangerous Brothers RPC1 firmware here:
The result is it's a 100% perfect flash, and the drive is now RPC1.
So for all intents and purposes, this unit is functionally identical to the Pioneer DVR-K06 (rebadged drive).
Tested both reading and writing various media.
I don't know if TDB read this forum, but I'd just like to say a big thanks anyway. Good job.
This was a replacement drive for a MatsuSHITa UJ-845S from an Acer Ferrari 4005WMLi laptop. As most people should know by now, this drive can not be flashed ... ever ... at all, due to firmware encryption. In the end, it actually died after less than one year of use; they are extremely poor quality drives, in addition to MatsuSHITa being idiots for being the only manufacturers in the industry to encrypt their optical drive's firmware.
CC'ed: to the rpc1 forum.