The official flashers refer to the exe files found on the firmware update page at the liteon website.
The exe contains the flasher and the flash update binaries.
The other flashers can be found on the cdfreaks forums.
FS0F is pulled from the liteon website. The latest version is FS0J. Have no problems with it so far... Leave me a PM with your email ID if you can't find the official FS0F.exe elsewhere.
Proud owner of:
JLMS XJ HD-166S DVD-ROM
Liteon LDW-411S DVD-RW