This is a solid studio and I would stay here again. First, it is spacious enough for one or two with a very comfortable double bed. The main room is plenty big for a long stay. More importantly, it is very quiet. The only neighbors I ever heard during my month-long stay were the ones directly upstairs and it was very acceptable - it is an apartment building after all. Compared to other buildings I've stayed in Paris, it was very quiet. Being on the 5th floor, it has no apartments directly opposite so it feels very private. The balcony on a sunny day is a delight and the sunsets can be great! Very good storage for hanging clothes and shelves for folded clothes.
Host was very prompt in addressing the small concerns that popped up from time to time, and everything was solved quickly. When I arrived in Paris, it was rainy on the first full day and a new travel umbrella was quickly provided upon request to replace the old one which was inoperable.
Building is secure, residents were always pleasant. It is located not far from Place de le Nation so it is a neighborhood for Parisians, not tourists. Many restaurants, grocery stores, etc., close by and very good access to multiple metro lines within short walks.
I enjoyed my stay. It is a very practical apartment and I would stay here again. Many thanks to Fabienne and Benoit for making my stay a pleasant one.