It's a very cozy flat in a very good location. The Louvre is about a half hour walk away. Notre Dame (which is still closed for repairs) is about a 25 minute walk. There is a metro station close by. It's also a 10 minute walk from Rue de Faubourg Montmartre, which has a ton of restaurants on it.
The shower can feel a bit cramped if you're tall and you will have to bend down to avoid the ceiling when going to bed, but those are just minor inconveniences. Overall, it's a great place to stay!