I have used these disks with absolutely no problem. The problem with the previous reviewer is that he/she tried to burn a Blu-ray disk on a Standard DVD Player/Burner. You can't do that! You must have a Blu-ray burner to burn a Blu-ray disk! As with other Hi Defination devices, it is usually the "user" that is at fault, rather than the product. For instance, many people [still] believe that just because they own a HDTV, they will see HD programming. Not so! The same goes for Blu-ray. Just because you bought a blank Blu-ray disk doesn't automatically give you the ability to burn a Blu-ray disk. Both Sony and Panasonic make some very nice Blu-ray computer drives which can both read and write Blu-ray disks. They aren't cheap, but you certainly get what you pay for.

Bought two of these to make backups of some work data and had problems writing to both. Since they are write once, it was a waste of money. Should have paid the extra for re-writable. The burner worked fine with the re-writable disc I purchased.