I spent two weeks in this apartment and I think I couldn't have asked for better. The apartment is modern, very clean and the room has all the options one could ask for, comfortable bed, fantastic cushions of various softnesses and, as if that wasn't enough, a super comfortable desk from which to work if necessary.
Apart from the quality of the apartment, what I found excellent was the location in the city of London. The apartment is located opposite Pimlico tube station, a quiet area with many restaurants of various kinds, from which you can easily reach most of the city (only three stops to Oxford Circus).
Last mention for Oskar and Fausto, who are two fantastic and very kind hosts who welcomed me into their home as a friend and offered me a hotel-level service.
In conclusion, I highly recommend this solution both to those who are looking for a medium-long term solution like me and to those who have to take a few days holiday in London.