The location is very good for Madrid, near the best places. Very odd for Madrid is that, at least for these days (end of August) at night and with the windows open... there was no noise. In Madrid, no noise is really rare. The view over the houses is nice too.
The price is good too, which counterbalances a few weaknesses. The airco is old, so not very powerful. The doors are controlled from an app, which is OK once the trick is understood, but the the door of the flat feels a bit flimsy.
Overall, it was OK for what we needed for these days at a very reasonable price.