I would highly recommend the place of Emma.
The apartment is really cozy, beautiful and modern. The modernity also adds to the cleanliness of it. The well-furnishedness (coffee machine, ceramic stove, TV etc.) takes the experience to the higher level. Combining these to the central location in a hip neighborhood with post-modern bars and restaurants as well as the fair price for Paris, this stay was a top experience. Last but not least, the quick responsiveness of Emma made the overall journey feel very comfortable.
The down-sides I noted were: the overall smallerness of the apartment than what I had in mind from the photos. This is however somewhat to my end - a less-hurried look at the photos would have made it clear. The second down-side was the cold of the room; even though the radiator worked well and fast after setting it before sleeping, it would stop during the night and the mornings felt rather cold.
Regardless, this stay was an excellent choice for me.