Great location within easy access of Gare d'Est, du Nord and Strasbourg Saint Denis. Lovely eateries and ambience in Saint Denis. Great that we could walk from Gare du Nord, straight off the Eurostar.
Laurent was super responsive and helpful. E.G. we had wifi issues on the second day and he saw to it straight away. Check in was easy and clear.
I would say however that the pictures are over-complimentary and we were slightly disappointed by the overall quality of the flat. It had no natural light (except some light coming in from two windows in one of the bedrooms) and felt claustrophobic especially as it was so hot in Paris (no AC), although there were a couple of fans. The bathroom door could be fixed, and the mould growing in the shower (probably due to no air circulation and humidity) could be cleaned.
That said, the location was great, we were out all day and didn't cook. We only have wonderful memories for my children's first visit to Paris!