NP here ya go........I only bought them last month and so far have only burn't 2 good DL's (when I say good they verified OK) DVDinfopro shows them as pretty poor when scanned. I even purchased a new Pioneer DVD drive to try to get them to work as DL media, no joy.
Not read anything about long term stability issues with them, only DL burning issues and drive compatibility.
PIONEER DVD-RW DVR-115D 1.18 (ATA)
Current Profile: DVD+R DL
Disc Information:
Status: Empty
Erasable: No
Free Sectors: 4,173,824
Free Space: 8,547,991,552 bytes
Free Time: 927:32:74 (MM:SS:FF)
Supported Write Speeds: 2.4x, 4x, 6x, 8x
DVD±R DL Boundary Information:
L0 Data Zone Capacity: 2,086,912
Changeable: Yes
Physical Format Information (ADIP):
Disc ID: RICOHJPN-D01-67
Book Type: DVD+R DL
Part Version: 1
Disc Size: 120mm
Maximum Read Rate: Not Specified
Number of Layers: 2
Track Path: Opposite Track Path (OTP)
Linear Density: 0.293 um/bit
Track Density: 0.74 um/track
First Physical Sector of Data Area: 196,608
Last Physical Sector of Data Area: 16,580,607
Last Physical Sector in Layer 0: 2,283,519
Physical Format Information (Last Recorded):
Disc ID: RICOHJPN-D01-67
Book Type: DVD+R DL
Part Version: 1
Disc Size: 120mm
Maximum Read Rate: Not Specified
Number of Layers: 2
Track Path: Opposite Track Path (OTP)
Linear Density: 0.293 um/bit
Track Density: 0.74 um/track
First Physical Sector of Data Area: 196,608
Last Physical Sector of Data Area: 16,580,607
Last Physical Sector in Layer 0: 2,283,519