After some of my older copies started coming up bad, I've begun a review of my 193 BD-R copies. I present here my preliminary data for your consideration. All disks were burned with verify and watched to ensure a successful copy when created. The type 1 Memorex are the oldest and were created in 2009. Type 2 Memorex and the Verbatims were created in 2010. To review, I've been ripping back to HD with a Sony BWU-300s which seems quite fault tolerant, and an LG WH10LS30, not so much fault tolerant. If the disks rips with both drives, I considered the disk to still be good and no other action was taken. If the process fails (read errors) on both drives the disk is considered failed. If the process fails with read errors on either platform the disk is considered marginal/failing, and the "good" rip is kept and viewed from the hard drive. If the viewing is successful (no glitches detected), the possible errors are considered recoverable otherwise the disks is considered failed (degraded playback). After reviewing 90 disks so far my results are as follows: Total failed disks: 21 Memorex BD-R (Man ID: RITEK BR2-000, type 1 (bright blue)): 17 out of 60 Memorex BD-R (Man ID: RITEK BR2-000, type 2 (dark blue)): 2 out of 20 Verbatim BD-R (Man ID: VERBAT IMc-000): 2 out of 10 Total Marginal/Failing Disks: 23 Marginal/Failing to Failed: 6 out of 23 (included in Total failed disks) Marginal/Failing to Recoverable: 12 out of 23 Not yet viewed: 5 out of 23 If you consider all Marginal/Failing disks to be failed then the Total failed disks rises to 38 out of 90. Leaving 52 Good disks. The remaining 103 disks to be checked are comprised of Memorex Type 2, Verbatim and Optical Quantum (Man ID: PHILIP RD4).