This apartment met our basic requirements- a great location, a separate bedroom (which was quite sizable) and a kitchen (which was tiny!). We had no issues with check-in; our train arrived later than the listed check in but Raphael was accommodating and had a very friendly concierge service meet us to let us in and give us the keys.

Pros:
-As mentioned before, the bedroom is a very nice size with ample closet space
-Nice furnishings, everything seems almost brand new!
-Location is excellent. Walk to Luxembourg or the Pantheon in minutes, get to Notre Dame in under 15 minutes, or take the Metro which is very close by. Very close to many restaurants/stores. Also, there is a cinema right next to the apartment- we didn't have time to go but it looked wonderful!

Cons:
-Small bathroom and unfortunately the nice rain shower head made a complete mess so we couldn't use it. Towels and shampoos provided but no hand towels/wash cloths or hand soap
-Even tinier kitchen. We had planned on cooking a few meals there but because of the small space, we were deterred. Also, no dish soap or sponge provided (there is no dishwasher so hand washing dishes is a must), no paper towels. We had to purchase some of those things ourselves.
-Washing machine provided but no place to dry!
-Very little space for trash, and we were uncertain where to take it once it started filling up
-There is a popular restaurant/bar below and on the weekends it got a little noisy/smelled slightly of cigarettes in the front room due to the people smoking on the sidewalk
-As some have mentioned, very thin walls. Be prepared for ambient noise. We were traveling with our 2-year-old, so we are used to the noise (and probably contributed to it)!

Arguably, most of my cons are things that some might be able to live without. They mostly add up to this: it wasn't easy to wash dishes or do laundry. While those things were easily forgiven thanks to the excellent location, they ultimately make it 4/5 stars.