Bottom line: I would recommend this place my friends, despite having to leave this place to a hotel during our stay and a few minor things that bothered me and my group. They were minor to us but they might be something you might want to consider. This place might not be suitable for a family with little children though.
It is centrally located, nearby the city hall (Hôtel de Ville) in a bustling neighborhood to make you feel energized and pumped up to be in the exciting Paris.
The building had a secure entrance accessible by a code entry and another locked gate. So you will feel safe. The building doesn't have an elevator. Walk up the stairs from the 2nd to the 3rd floor where the loft is very narrow, spiral & not easy. I did not mind the stairs to the 3rd floor except when I had to carry up and carry down our suitcases.
The apartment was well maintained and clean with nice furnishings. The shower stall is small compared to the American shower stalls. The shower glasses aren't frosted so it's pretty to look at. But the glass door doesn't seal completely so be ready to step out the shower to a puddle of water. The place had plenty towels to mop up the water so not a huge problem. The bathroom sink counter is too high. Smaller persons or children might have a hard time.
Now, to a reason why we had to leave this place. We spotted mouse droppings over the course of the first few days. At first we thought it might be because the place had been empty and that we were on the top floor. The building is old and located in a populous area so, yes, mice are around. We understand you can't completely control pests. But when we found the mouse droppings inside one of our suitcases, we could not stay there any longer.
So why would I still recommend this place? It's because of Paolo. He responded immediately to our messages. He took action right away to take care of the pest problem. When we decided to leave, he was understanding and refunded us through Airbnb. He did everything right to be an accommodating host and took immediate action when the problem arose.
I did not find any other reviews complaining about pests. So I'm guessing it's not a frequent occurrence. So your stay might not be like ours.