I have both and LOVE both. The mezzo was one of my first shoulder bags I bought. It is my work horse of a bag. With that said, my mezzo is used...and abused!!! But well loved. The totally is an updated version, IMO. I love the side pockets and the pockets inside the bag can't be beat (which the mezzo lacks). I like the bottom of the totally better since it shows less wear. I think the mezzo must have a purse charm (at least mine must!!!), cause it tends to be slightly plain. All in all, both are great bags. I think the totally MM is a very comparable size to the mezzo, if that helps.