On Lite-Ons page for Fimware updates this text moves from the left side to the right all the time.
"Note: Once the drive has been upgraded to new firmware, it can NOT be changed back anymore."
So now I wonder if somebody have tried so put an older firmware in their Lite-On LTR 52327s, say go from R52QS0C back to R52QS0B and if that worked without any flaws.