My partner and I stayed at Stephane's place for a 5 day trip to Paris and we highly recommend it. The apartment itself is lovely - you have everything you need, the location is great, and on top of everything you also have a view of the Eiffel tower (!!!). Although Montmartre is slightly away from the centre of Paris, it's actually the perfect balance of being close to the action but far enough away that it feels peaceful. Also, Montmartre is such a lovely area in and of itself - lots of shops and cafes and boulangeries around!
Stephane was super easy and prompt to communicate with, and he was also really flexible with our check-in and check-out times which we really appreciated.
We highly recommend staying at Stephane's place for the perfect getaway to Paris. Only thing to keep in mind is that the apartment is on the top floor so there are quite a few stairs up and down, which was a good thing for us considering how much we ate every day!