1. from the manufacturers website
2. very easy.and very similar to a bios flash.ist read all the instructions on the process beforehand and if nesessary print them out then the firmware is downloaded to a msdos boot disc.the computer is set up to boot from the floppy first via the bios and the computer is then restarted with the disc in the floppy drive.then follow the instructions.is usually as simple as "do you want to continue updating firmware" press y for yes n for no etc.
pitfalls are a dead drive if the wrong firmware is flashed.you need to make sure it is for your exact model.a power cut mid flash will render the drive useless too so make sure its the correct update and dont do in a thunderstorm.
benifits are usually improved handling of certain media types like cdrw or 3inch cdrs or certain brands of disc.or in your case dvds.
your drive is actually an oem panasonic jobby
i cant see any firmware updates for your drive on the panasonic site and they refer you to your computer manufacturer for all updates.there are firmware updates for this model elsewere like click here for instance.but would check out the your computer manufacturers website first because there is also an sr8582 b model.