We had a wonderful stay in Nick's flat for 8 nights. The location was very convenient for public transportation, with a bus stop right out of the door and a tube stop just about 5 minutes away (Earl's Court - District and Piccadilly lines). It was an easy walk to get groceries, plus we were able to get delivery very quickly from a number of different places.
The flat was just as described with two big bedrooms and two full bathrooms. It is down one flight of stairs, and there is no lift, so be aware of that if accessibility is a concern. We found everything to be very clean and comfortable. The beds were great, and the blackout curtains in the bedrooms really helped us fight off the jetlag. The bath towels were plush and large (a welcome change from tiny hotel towels), and we were even provided shampoo and bath gel. We made good use of the washer/dryer - it was terrific not to have to bring 9 days worth of clothes.
Nick was extremely responsive to all of our questions, and he answered me very quickly, even with the time difference (we are in the US). I would not hesitate to recommend this flat, and I hope we can stay there again if we are lucky enough to return to London.