I have just installed an 18 month old Samsung 830 from the HDD slot into a OWC Data Doubler in my late 2011 MBP. It is being shown as 6GBs linked and connected at 6GBs in system profile. It seems to be running normal. (Maybe slower to boot) I have used blackmagic to test it. I should have tested it BEFORE I moved it but I didn't!! Blackmagic is showing a constant 340MB/s write but a fluctuating read of between 200MB/s and 440MB/s.! Now before I swap it back to the HDD slot to test, Is this a common problem with the already known list of MBP sata speed superdrive problems?! Or could it be the SSD just needs reformatting and a clean OSX install?? Thank you.