Sorry about my type 2 posts earlier... It should have be "happened". Actually it looks funny anyway.
if you need Bitsetting to make +R media more compatible (and also use +R/RW media) the Bufallo 8.50 is the firmware to go for. Otherwise, 1.4 or 1.5, it's your choice. It's always a little trial and error game.
You can find al the firmwares HERE.