Given the design and being that it’s leather bag, it can only be so dressy (it’s not a satin clutch you’ll wear with a black tie dress). In my opinion, in this case one is not going to be a lot dressier than the other; they are both small bags. I would pick the one you like best on you and if you want more versatility (day to night), go with the one that fits more things.
For a few hundred more, I would go with the MM. I don’t know your lifestyle, but when I buy expensive bags, I like to buy them and be able to use them in as many occasions as I can. The MM is small enough to wear with a dress at night or wear it during the day with a blazer but want to carry a few more essentials with you. I don’t see the advantage of the small one in this case.
If you want a strictly evening bag, I would go with something dressier than this.