I have one of those Mosella ones, and it does not really make it much easier .Yes you can stretch a small band to full size of bait but then it's tricky to get the tines off without pulling the band off again.
Use it for a full session and you'll get used to it. I'll bet someone using this tool can band 10 pellets while someone using fingers is still faffing about with two or three. And in the dark with these old eyes, make that 10 to 1.