David, I read some reviews on roll film backs. This one you are showing is a lesser quality one according to the forums.
The one I tried had good reviews, but it was defective. I would not want to risk any purchase without having the right to return.
The other issue - the break-even point is about 100 rolls of 120 film for the cost of purchase, or at the least, that's the cost of roll film and panoramic ratio convenience for overseas travels.