Hi Bevoray - What an exciting purchase you have before you. I own both the YSL Large Muse and the Ferragamo Marisa (siblings to the bags you are considering) and I personally favor the Ferragamo over the YSL. As far as functionality goes, I am indifferent between the medium Muse and the Gamo satchel. Volume should be similar, with the difference in functionality being the dual zippers on the Muse and the single zipper on the Gamo. The only reason why I prefer the Gamo is because the leather is softer and molds to my body. I would also try on both bags, as I've found I have less wiggle room with the shoulder straps on the Muse than with my other bags. Good luck with your decision.