Looked over the review again, and while it seems the drive turned in creditable write quality with all but the most rotten codes, the not very old firmware has poor speed compatibility - though if the 4x on 16x results are representative of the fallback strategy for media the drive doesn't know, then there shouldn't be much that would fox it.

At the moment, it seems that you need to be able to buy a sample quantity of 16x media, or verify support in advance - no point paying extra if it only goes at 4x!

Also interesting to note that several of the 8x pushed to 12x, actually didn't go - not sure if ther's a quality evaluation element in that?