Have to agree with rockford, in that the "Plextor" made drives were good (Have the 716 and 755 Sata drives), I think there new line 8xx are rebadged (I think Samsung or pioneer).
I had all, Sony (oldest drive I have), Samsung (just replaced with an LG Dlu-ray writer). Not a Big difference in quality of scans. Which model is the "best" differs with Model/timing. If I was buying one, I would probably go with samsung, Hate Sony (as a company) - but at same price as competitor would by, BUT would not pay a premium. Liton use to make some great drives but middle of the road. Note I own 3 stand-alone Liton Recorders - they have worked great. The drive went out on the 5001 and I replaced it with a internal computer Liton drive - No Problems
Current computer has the Plextor 755SA and the LG H20L burners. Samsung drive on self, and BU computer has the Plextor 716 Sata. Wife's Computer has the Sony.
PS - Might try some of the "CD/DVD" forums such as CDFreaks and CDinfo