Good: the space is large, clean, and comfortable. It was great for my friend and I because she took the living room (which had a door), and I took the bedroom. It's also right at a main metro station, which made it easy to get around, and it was only 15 minute walk to the 4th district where Notre Dame is.
Not so good: Communication was slow and confusing. I messaged the morning I was to arrive to see if we could check in an hour early. I never heard back. Nearly an hour away from Paris by train, I messaged again when I noticed no street number was included in the instructions. They replied then, but only with the street number, and nothing about us coming early or how to pick up keys. It wasn't until we were standing inside the building's lobby realizing we had no idea what apartment we were going to that we finally had to call and get all our answers.