We thoroughly enjoyed our stay at Adrien's flat. Would definitely recommend it and would stay there again. First and foremost the rooftop patio is outstanding. We enjoyed sitting out there every evening, enjoying both the views and the cool breeze as the sun set. The view back toward the city (from the kitchen or around the corner on the patio) is not too shabby either... you can see downtown London including the Shard and other landmarks!
The apartment itself is quite nice, with a comfortable bed, sofa, and coffee table along with a fully functional kitchen (including a washer for laundry!) and clean bathroom. Since the apartment is on the rooftop and has windows on two sides, the breeze flows nicely through the whole space, keeping it cool and fresh. Note: no AC, but frankly we didn't need it even in early August because of the wonderful breeze. Note also that although there’s an elevator, when you get to the top you’ve still got one flight of stairs to get up to the apartment. Not at all bad, just something to keep in mind.
The location is also very convenient, as it is close to various subway lines, the Euston rail station, and bus lines. We found it extremely convenient being just steps away from the 24 bus line, which takes you right downtown to the Westminster/Big Ben area. We found riding the bus each day so much better than taking the subway, as it is both a bit less expensive and gives you the chance to see the city!