I booked Alexander's flat when my parents were visiting in London. Alexander proved to be very good host: he promptly answered all questions.
Location is really good - very close to both West Kensington and Barons Court tube stations, also quite close to all museums and other attractions in South Kensington.
Flat itself is freshly renovated, in an excellent condition with all amenities and fast WIFI. Show room is amazing!
Overall highly recommend