The apartment is great! Such a nice place. Very clean and tidy. It's very central and close to metro stations, you can easily walk down to Notre Dame and the Louvre. There's a folder in the apartment, containing recommendation for close by cafes and restaurants, definitely worth a look, there are lots of them in the area, which is not too touristy either.
The apartment is very small, but my girlfriend and I had no trouble with that. If you don't travel with just cabin luggage like we did, you might find it a challenge to move your big luggage through the corridors into the apartment.
All in all I would say this is the place to stay in Paris, I can definitely recommend it and will be back next time I am in Paris.