We stayed just 1 night in this apartment as it was within walking distance to the US Embassy. Everything was to our satisfaction and the apartment was very clean and spacious for London.
My mother stayed on the sofa bed which she said was comfortable although it was a little noisy with traffic throughout the night. It was a warm night so we had to have to windows open slightly however the apartment itself did not get too warm for us.
The bedroom on the back was a little quieter so we got a decent nights sleep.
Tea and coffee is provided which was a nice touch and there are grocery stores near by for any other extras you need.
Good value for money for London, a hotel would have cost us 3 times as much