Good budget option.
The location is good - two metro stations, plenty of bus routes, a supermarket & places to eat all close by. Easy to walk central Madrid from here.
It's quiet in the room & street, yet in the centre.
Communication is very good. You aren't met by anyone in person, but told in advance which room you are in and whereabouts in the building (looks like a few rooms here are let out.)
The room was a basic and functional. It was a good size and had plenty of light. We didn't find the bed comfortable. It's so soft that the lighter person spends the whole night sleeping on a slope towards the heavier person. The pillows were quite hard. We would have preferred a thicker duvet. It may be possible to ask for one. As we were only there one night, we did not.
The bathroom would benefit from renovation, but is functional.