So in short, this is a very nice apartment, placed in a good neighborhood with perfect access to the major attractions.
I liked the street, I liked the quiet building and I liked the atmosphere here. The decor is nice, it's very bright in the morning. There's an elevator, which surely isn't a given in these old buildings.
The host is communicative, nice, and easy to contact in case you need to. I have no reservations whatsoever, and would gladly stay in the same place the next time I'm in town.

A tip: the first time you get there and don't want to get lost - remember you need to get two separate elevators to get to the apartment. The first one only takes you up one floor, and it took me a while to figure that out :)