Although I'm just speculating I would assume the blue box is their standard cleaner as oppose to the medaille d'or which is their premium range. Saphir are pretty tight lipped about what goes into their products so I don't know the exact difference I'm afraid. Essentially it will be a differing ingredient set up like the renovateur vs renovator scenario (renovateur has the more expensive mink oil in, renovator doesn't).
I have the black boxed medaille d'or suede cleaner and it's fantastic!
Thanks for your response. Do you think the $9 price difference would be worth it?
Does anyone else have information about this?