Great place in a great location. A few things in the the property didn't work (e.g. the bathroom vent and some of the window shutter locks), but that's pretty normal from an AirBnb in our experience.
Very close to everything you'll need during your stay. The metro is down the block. A great coffee shop is only about a block away as well. There's a 24 hour supermarket near the metro. Within a few minutes is a street full of bars with outdoor seating.
The Lavapiés station let's you easily get to all different parts of the city - 2 stops to Callao, 3 stops to Plaza de España. The city is also very walkable - you can get to most of the popular places within a 20-30 minute walk.