We stayed in this apartment for five nights and, overall, the experience was very good.
The apartment is really well located. Right in the heart of the Madrid centre, yet rather quiet. Although the district itself does not look very appealing to the eye (and sometimes to the nose), it does not really matter because of the proximity to everything. And it still feels quite safe to return to the apartment at night.
The host is very responsive and flexible when it comes to special requests about check-in and check-out times. This kind of service is what a traveller wants.