The flat was exactly what I needed for our stay in Paris with my wife and daughter. The property was clean, easily accessible, and in the perfect location near the normal tourist attractions that we were in Paris to visit. The neighborhood was safe and comfortable, and the cafes downstairs were perfect for coffee or dinner.
The flat was well-appointed, and all linens were provided. The beds were comfortable, the living space adequate. Keep in mind going in that you're staying in an old building so the rooms are small, but that didn't bother us one bit because we spent so much time away and exploring.
My only complaint is that I was anticipating having someone meet us at the flat for check-in, but a few days prior to arrival was given directions to a nearby hotel to collect the keys. It wasn't terribly inconvenient, but having gotten off a red-eye and have to explain to our driver that we needed to make two stops was a bit of a complication. Knowing up front would have been nice.