raynb PM-ed me with a few questions, following on from a discussion in this thread.
I hope you don't mind me answering them in the forum. This allows other members to contribute to and benefit from the answers.
None of the Samsung SH-S203 or 202 drives should cache audio data. There is a lot of erroneous information out there regarding drive DAE features. Software like AnyDVD or DVDFab Passkey running in the background interferes and will produce incorrect detection of caching.
Caching is not cause for concern with secure audio extraction, so long as the software knows how much data the drive caches. It can then compensate by re-reading in larger chunks. This slows things down, but only when errors are detected and re-reading takes place. So long as the software knows the correct cache size and compensates correctly the results will be as reliable as a drive which doesn't cache.
I would ignore the dBpowerAMP drive accuracy list as it does not take into account the condition of the discs. Therefore regardless of the volume of data, the range of data they are gathering cannot possibly support the conclusions drawn.
If you look at the 2014 dBpowerAMP list you will see that the Sony DRU-810A is in the midfield and the Philips DVD8701 second from last. As any CDFreak knows, these are exactly the same drive - a rebadged Benq DW1640. The difference in firmware could theoretically make a difference, but (almost) never does, especially with modern drives.
In my experience, how a drive behaves & performs when reading damaged CDs is mostly dependent on the chipset used.
There have been many other cases of drives with identical hardware being ranked very differently. Also Lightscribe & non-Lightscribe versions of the same drive, which as far as DAE is concerned are probably identical in both hardware & firmware.
Also they are ranking drives to 4 decimal places and the entire list is covered by less than 1.3 percentage points, a margin I consider statistically invalid in the circumstances.
In my opinion, all their data proves is that if the CDs are in reasonably good condition and the result can be verified using Accuraterip, any modern optical drive will do the job just as well as any other.
It is only when discs have significant damage/degradation, or if there is no external checksum to verify the result (i.e. Accuraterip), that the choice of drive becomes important.