The flat is very nice, immaculately clean and in amazing location (next to Sloan Square tube station). It is on the top floor with light coming in from big windows and skylight from two roof lanterns. All sounded nice, however, our stay coincided with the big heatwave in London. Indeed, it felt like a greenhouse and the flat was much hotter than the rest of the building.
The staff was very nice and helpful in trying to make our stay as comfortable as possible. However, they spoiled the initial good impression in the last few minutes of our stay. Due to the extreme heat and sleepless nights, we were not able to get ready on time of checkout. At exactly 11:00 am we received a knock on the door to ask us to get out. We asked for an extra half an hour to allow us to get ready. However, we were told it is not possible because the cleaners have to come in at 11:00 to clean the flat and we should allow the cleaners to start cleaning while we are getting ready! Of course we refused and at the end we were allowed an extra 15 min, during which time the cleaner was standing impatiently outside our door. We expected more consideration and understanding.
Despite the glitches, we might still come back, perhaps during cooler weather though.
We definitely would not recommend the flat during hot weather unless changes are made to make it cooler like, for example adding blinds to the alcove window and the lanterns.