Amazing location,lot of restaurants around,30min walking distance to the musuems (Prado,Sofia Reigna)or Royal palace,if you want to visit El Escorial you can go directly fron Sol with the Cercanias train. Good and fast communication,modern flat with everything you need,very accomodating host,we were able to leave our luggage in the flat longer as out flight was in the afternoon (little tip you can take the Cercanias train from Sol and with just one stop you are on the pink metro line bound to the airport),can get a bit noisy outside in the evening as you are in the middle of the action so just have an extra Sangria :)