Ah... are you sure that the LVW uses a LDW-401S? I thought it used a DDW-401S or something.
In any case, a LDW-811S should work just the same as a LDW-401S. You will probably be better off renaming the LDW-811S to a LDW-401S than to actually flash it with a 401S firmware.
I'll move this thread to the LiteOn DVD Recorder forum as there is more info there about replacing the drives in the LVW models...