I have a 2009 27 inch, 2.8 GHz, i7 iMac with a 1TB hard drive and Mac O Rama in Reno installed OWC 960 GB SSD drive with the data doubler adapter. The iMac now has internal two drives. The optical drive was removed. I was using the SSD drive for booting. This has been running just fine for the last five weeks.
I have two external backup drives, one for SuperDuper and one for Time Machine.
Today I setup Time Machine to backup the SSD drive to the internal 1 TB hard drive. After a couple of hours I came back and the screen was black. Held the start button down to shut every thing off. Then restarted and the SSD drive does not show up. It restarted from the original hard drive.
Ran Disk Utility on the the startup disk, nothing. Then shut down waited for a minute and restarted with the "option" key held down, the SSD did nor appear. Ran Disk Warrior v4.4 and still no SSD.