']I don't have any SONYD21, but I have a 3 month old MIJ SONY08D1 that is showing quite signifigant deterioration. PIE levels up are ~40% across the board. Maybe I'll post the scans later.
This is a MIJ Sony 8X DVD-R burned on March 6th. It has been stored in a full size jewel case in a black box in a 18-25C, 35-70% humidity environment. This disc has not been handled more than once or twice since being burned, and it's virtually free of dust or scratches.
First image is the original scan, and second image is the scan from last night. As you can see, PIE totals are up ~33% at it looks like we might be beginning to see problems at the outer edge. IMO, there is too much evidence pointing to serious lifespans with Sony media from any country, for me to use or recommend it.