OCZ replied today and it's interesting what they wrote.
Firmware updates should only be applied if the drive is malfunctioning similar to your case. We do not recommend users to update the firmware if the drive is functioning properly. You can apply the firmware update without the secure erase and see if the issues have been resolved. If they haven't we then recommend that you perform the secure erase and a fresh install.
As for image cloning, SSD Controllers have to translate logical blocks to physical nand locations. This complicates mapping snapshots when imaging 'incrementally'. If you decide to clone your drives, please use whole disk images as they include all tables in the disk signature and are preferable with your OCZ SSD. Please also perform the clones from external bootable media rather than internal to the OS.
Two questions immediately arose, which I submitted.
Thank you for your informative reply. I wonder if and how cloning could cause the kind of failure 3 of the 4 SSDs had. I mean, the drives worked fine for two or more months before suddenly becoming unrecognizable to any BIOS as drives. Can imaging actually lead to this kind of failure months later?
Secondly, you write that "Firmware updates should only be applied if the drive is malfunctioning similar to your case." In the case of this latest drive, which still shows up in BIOS, I can see how your firmware update software might still communicate with the drive (and I'm having a tech try that as I write this), but can your firmware software update an SSD that the BIOS cannot see?
I plan on also asking what exactly they mean by "external bootable media. Can it not be Windows 7 on another HDD? Their reply also raises a question that I think many individual tech-savvy SSD users might have: can programs like Tereabyte's Image for Windows (or DOS), Acronis Trueimage, or one of Paragon's programs be use to perform the kind of disk copying or imaging that OCZ recommends? For that matter, there's "imaging" and there's simply copying an entire drive. "Imaging," at least to me, means to create a .IMG file of a partition or drive using a program like Terabyte's Image for DOS. It's akin to an intermediate file that must be restored to a drive to end up with what you originally imaged. "Copying a drive," as one can do with Paragon Partition Manager, is quite different. I need to ask OCZ if simply copying an SSD to another drive, like an HDD or another SSD, is possible. And I will.
Any constructive comments will be appreciated.