We had a great time in Johns flat. John was very nice. It was very easy to communicate with him. He answered every email within a few minutes. In addition he had some useful hints for our visit in London e. g. where to park our car.
We stayed there with five persons and there was really enough space for us all not just for sleeping but also for living. Two from us slept in the "parents room", two in the "bunk bed kids room" and one on the sofa bed in the living room/kitchen. Water and heating were warm. Wifi and microwave worked well. We always ate out so we didn't use the oven.
The flat was as described and nearby everything you need: underground, supermarkets and especially Hyde Park. And all that for an very attractive price.