We spent two nights in this apartment and it was great for our family of four and very clean. It's close to the Metro and a good base to explore Paris. The shower was hot and powerful. The mattresses were a little too hard for our liking but I still had a good nights sleep.
There was a slight issue with the code at check in but Nordine and Florent were easily contactable and quickly sorted it out.
One thing I wasn't aware of is that the apartment is very close to the red light district. This was a problem at all but did prompt lots of questions from our children! The apartment is tucked away from the main street and very quiet, we felt very safe there.