This is a lovely flat with a location that can't be beat. There are so many restaurants and shops near by that you'll have no issues finding great food, wine, coffee or whatever you fancy. It's so close to the Eiffel Tower that you can't help but to keep walking over to look!
We were unfortunate enough to be in the height of the Paris heatwave, so the main floor was very warm. Only the upper floor is air conditioned (where the bedrooms are) so you need to make sure you keep the door separating the floors closed.
The other problem with the heatwave was that it caused issues for the elevator. Stick to the stairs unless you really have to - and even then use caution. We got stuck but with some assistance were set free. The elevator guys were immediately onsite after to work out the issues but being trapped in a tiny hot elevator was rough experience. That however is more reflective of the building than of Xavier's flat.
Otherwise expect a spacious and unique Paris apartment that is very homey. Great if you have kids because of the neat loft space. Just be sure they are ready to climb stairs because it's 6 flights up to the 5th floor in Europe!
As per other comments, due to the air drying of towels, they are not soft, but there was no shortage of them.
I recommend this place in particular in the spring or fall. Can be a bit challenging in a heatwave.