The location is hard to beat: lively, walkable and with plenty to do around the apartment. The apartment itself is super nicely decorated and appointed. Not that you want to spend time there, as Madrid is outside the door to be discovered.
Only (small) gripes are the stairs are a little steep, was with there with my mother who struggled - but made it up and down each time. Also, the area is super lively at the weekend during the night and early morning, if you sleep with the window open, you will hear stuff at night - but as you are a bit higher up, it was nothing even the light sleepers in my group couldn't sleep through.
Service was great, and super responsive. Would come back in a heartbeat.