Great spot in a real central Madrid neighborhood. The apartment is clean and provides what you need as a base. The two bedrooms are a decent size and offer plenty of closet space.
If anyone is a light sleeper put them in the bedroom furthest away from the adjoining apartment. The walls are very thin - on two occasions the buzzer for our unit was rung from the street and the people in the next apartment answered thinking they had been buzzed. This created only some amusement for us but we did wake up one morning feeling part of the conversation of our neighbours.
Overall I recommend it if you don't mind the stairs and appreciate the extra exercise.