The flat (or should I say "apartment" :) ) was really good, perfectly clean and handy. Even if we didn't stay much in the flat except for sleeping.
The neighborhood was amazing, because the flat is in the center of Williamsburg, everything is close by, and it is really good to explore the entire New York.
Kells is a great host, he wasn't here from the middle of our stay (still reachable by text) but his mate Dave (who is living in the flat) was really nice too and answered our questions. Kells was very accomodating with our check in (I landed late at night at JFK) and for the checkout, we were able to leave our luggage in the flat for the last day as our flight was in the evening.

We recommend the stay there ! great experience and great location to visit New York.