My son, his girlfriend and me spent in this apartment 6 days and it was great. The place is as per the descriptions and everything is working fine.
Neighborhood is incredibly cool. Most probably the most interesting area to stay in Paris if you like the design shops, good restaurants and to be closed to the ancient Paris area.
Walking distance to very beautiful places like Notre Dame, Hotel De Ville, Pompidou, and with the Metro station only 300 Mts far, it's very practical.
If I would have to suggest an improvement, would be some courtesy services like receiving the guests with soaps in the bathroom, shampoo or detergent in the kitchen. Little details count when you are traveling and would add value to the apartment.
I know the owner offers to sell those implements before arriving, but prices were not convenient and paying USD 200 per day would justify simple courtesy details that would increase the pleasure to stay in this apartment.
Good and advisable place to stay.