I had a lovely stay in Laure's apartment. It's a fantastic location that's close to everything while still being calm and quiet. There's a wonderful bakery on the first floor so you wake up to the smell of baking bread, and quaint views of Parisian rooftops out of both rooms.
Quick notes: The apartment is located on the seventh floor (6th if you're counting in French) and there was no elevator, so it may not be appropriate for people who are handicapped or have limited mobility. But if you're visiting Paris you're probably already doing plenty of walking and I enjoyed the exercise :)
The bathroom is also quite small and while I was very comfortable, the shower could be a bit cramped for someone on the taller side.