justamacguy wrote:
The real fact is that nobody really knows what the average life span is because nobody has been around long enough to see what it is under natural conditions. All of the test that are done are based on artificially aging the discs.
Very true. But it is well established that organic dye based optical discs degrade over time because of the effects of temperature, humidity, & exposure to light. (This includes "gold disc" & similar reflective metal types, which refers to the reflective layer below the dye.) Most accelerated life tests don't include exposure to light, but a very carefully conducted one by the Naval Air Warfare Center Weapons Division at China Lake did.
In that test, the M-Disks were the only ones that didn't fail. But more significant, at least to me, were the results of the prescreening done to get samples that had acceptably low initial write errors. The researchers discovered that every brand of drive tested did relatively poorly with some brands of optical media & that no brand of media, not even the highly regarded Taiyo Yuden & Verbatim ones, worked well with all of them. In fact, variations among same-model optical drives were also significant.
That suggests that users need to be careful about selecting the most compatible brand of discs for their particular optical drive, & that the best one won't be the same for everyone. It also is further confirmation that for maximum reliability it is important to verify each disc after burning it, significantly increasing the time it takes to make archival quality backups.
Since it is relatively time consuming to burn discs to begin with & their capacity is relatively low, I strongly doubt that most users will consider them a practical alternative for their large scale or frequent backup needs.
And, to your last comment, “…you will have to buy an external drive anyway.” That is what worries me with Apple.
Please note that all the optical drives currently available capable of writing to M-Disks are tray loaders that work only in the horizontal orientation; there are no slot loading ones that Apple could fit into even much thicker iMacs. The same goes for optical drives that support faster than 8X burn speeds. A lot of users want that -- it is one of the complaints many have about Apple's "SuperDrives," & why they end up buying a higher performance external burner.
So basically, Apple can either include an optical drive in a slightly thicker new iMac that will satisfy the needs of relatively few users & quite possibly will become obsolete as better optical technologies emerge, or do what it has done, which is include no optical drive at all, without in any way preventing users that want one from choosing one of the many external drives that will fit their needs better than anything Apple could provide.
That doesn't worry me at all.
