I don't know what the differences are exactly.
1/ They were both made around the same time.
2/ LiteOn made both firmwares.
3/ The LED is different for the Sony.
4/ They both share the same common MCC003 bug (which suggests that they probably just reused code)
5/ My guess is that they are more or less identical, but I can't be 100% sure of that.
Only the manufacturer (LiteOn) would really know what all the differences are.