The biggest advantage of the 6x8 back is that all your negatives will fit on a single Printfile sheet

Actually, the power wind is handy, and the built-in 120/220 compatibility isn't bad either.

And when someone refers to a 4/3 format camera, you can whip out your RB67 with this back and say (preferably with an Australian accent) "4/3 format? Now this is a 4/3 format!"