The apartment of JB is perfect. It is clean, spacious and fonctionnal.
The location of the apartment is good, 3 min walking from the metro and around 15/20 min by tube to the city center.
The communication with JB was always easy and he welcomed us very nicely. He was very flexible with us to let our luggage in the apartment when we needed.
The only thing I would say, is that you need to get used with the noise of the street (in the bedroom next to the street), but it was fine in the end.
I would definitely recommend this flat to stay in London !