Location is special: the elegant little slice of neighborhood between the Prado and the Retiro. Definitely not busy but a few cafes and restaurants close by. (I liked Jeronimos - breakfast - and Cafe Murillo - lunch.) Prado and Retiro park are literally steps away on either side. 10-15 minutes or so walking to main tourist districts and their countless places to eat and drink. You can also explore less touristy neighborhoods from here very easily. Try the other side of Retiro. Lots of tapa bars and restaurants off the tourist track.
Apartment was fine. In 1970s-era seven storey building. Comfy bed, great AC, good light, excellent wifi, no noise. Scary narrow balcony but at least a place to sit outside and hang up your laundry. A bit of a ghost building. In 6 days I saw two other people, including the doorman.
The hosts provided excellent suggestions for places to eat and drink and visit.