I plugged in the exchanged AD 7260 (the first one was defective), although they are supposed to be the same drive, it was able to read the disk without any difficulty.
So it seems that it's not just a model/brand thing, but a per unit thing.
Indeed, they are rebadges.
Are Blu Ray drives built with higher quality assurance than DVD writers? Maybe the industry is focusing their manufacturing power on BD drives now?