My friends and I had a lovely stay at Pedro's apartment. It is exactly as described: in the middle of the city, clean, comfortable and very well maintained. As others have mentioned there is some noise from the street at night in the twin room (not the double, that's very quiet) but you must expect this when staying this central. The apartment was well equipped and beautifully furnished. It is easily accessible from the airport (took us about 40mins via bus and metro) and there are several metro stops within minutes walk. I would recommend anyone wishing to stay in Madrid to use this apartment.