I had a fab few days in Margaux's little flat. The location was terrific, I walked the vast majority of the time. Outside the street seems bustling, but being on the 4th floor (she's not kidding about those steps) the flat itself is delightfully quiet. The place was very comfortable and I was surprised by how easy to manage the fold out couch was.
My one slight complaint is the wifi was not as reliable or fast as I would have liked but then I'm young and pretty attached to my phone and had quite a bit of organizing/planning to do while there. Bearing that in mind I think it would be totally adequate for most people.
Again, I had a lovely time and would happily recommend this place to anyone (also check out the bakery Blé Sucré around the corner, best pastries/bread ever)