Among my experience through Airbnb, It was the best place I've ever had. The important thing is that they are living there, so everything is like a real home.
The flat was exactly similar to the pictures and it was really clean. The neighborhood was great!!! Everything is in about 10 min walking and night life is really cool. There are lots of pubs and restaurants around and during weekend there are lots of guys hanging out.
Unfortunately, we did not have the chance to meet Sébastien & Marion, but everything were well organized prior to our coming (We arrive there at midnight and we didn't have problem).
The apartment was modern and it seems that it was recently renewed but it was at 5th floor and there was not any elevator (for us it was not a problem, in fact it was just an extra exercise ;-).
I extremely suggest it.