Don't delay, book this apartment. Spacious, quiet, yet perfectly positioned accommodation.
We visit Madrid 2 or 3 times a year. This was our first AirBnB booking, and (thanks to Sol and this apartment) it was about as faultless an experience as a person could ask for.
We will absolutely be keeping this apartment at the top of our list of preferred places to stay when we return to Madrid later in the year.