Ramon and Rafa are great hosts - immediate email and/or text message communications were made whenever useful, and they were both very forthcoming with any of my requests.
The flat is ideally situated in the heart of Madrid, with plenty of restaurants, bars, and attractions nearby.
It is very spacious for 4 persons, can accomodate 6 if necessary, is beautifully decorated, well furbished and well protected (several locked security doors). There aren't many openings onto the outside, but given Madrid's weather in the summer I am sure this is a further advantage ! (I stayed in the winter, so I didn't mind).
There is also a guide in the flat with all recommended addresses in the vicinity, which is a great idea indeed.
I can only warmly recommend this place to any traveller who would like to stay in central Madrid.
Thank you Ramon and Rafa !