I wonder if you can add support for HD-Burn with the OptoRite firmware.
The author has just updated his review on the DRU-530A, and he has no problem using the Optorite firmware version 120E on the DRU-530A, although not much has changed. He also noted that there is still no support for reading and writing HD-Burn discs with the Optorite formware. Too bad he didn't test if it could write at 8X using the certified 4x +R discs.
http://homepage2.nifty.com/yss/dru530a/osony.htm
So there is no doubt that the Sony DRU-530A is an OEM model of the Optorite DD0401 with the HD-Burn function disabled. The question then becomes why would anyone wants to pay $100 more to buy a Sony labeled Optorite OEM with no HD-Burn support? I guess Sony marketing people had better find some reasons soon before people figure out what's going on.
As for the inconsistent results between K-Probe and UM Doctor Pro II, the author has mentioned in another topic:
http://homepage2.nifty.com/yss/um2/um2.htm
and the reason he chose to use sum 1 ECC instead of sum 8 for K-Probe was because the results were more compatible with those from UM Doctor, which were supposed to be measured at sum 8 also. Of course, considering the measurement errors introduced by using the Lite-On 165H and Optorite DD0203 as separate readers, it's anyone's guess what they really mean.
I personally don't put too much faith on either program, but when some discs (TDK and Maxell) burned by the DRU-530A cannot even be read properly, there must be some problems unless the author happened to get a defective unit.