Taiyo Yuden claims a 70 year shelf life, but they have only been around for what, 8 years tops?
The company itself has been around for 60 years. Granted, they haven't been optical discs for all that time, however their oldest discs are coming up for 30 years now, so there should be some indicator of quality by now.
They laughed at Einstein. They laughed at the Wright Brothers. But they also laughed at Bozo the Clown. -- Carl Sagan