We had a great stay here. The location and views don’t get any better. We didn’t use cabs or the subway much since it’s walking distance from all the spots in Madrid.
The mattresses were firm and very comfortable. The shades in the rooms made it very dark at night to the point that it was a bit hard to wake up the next morning :) Though with the shades open in the day, the natural light is great and quite beautiful close to sunset.
My friend and I worked from home here for a month and found it quite comfortable. Wifi download/upload was generally at 20-100 mbps. Service was sometimes spotty from the farther bedroom, but not a big deal at all. We also brought a fire stick and had no problem streaming video even with a VPN turned on. The kitchen was good for light meals in the week and there was a nice combo washer/dryer right across the hall.
Highly recommend for either long or short stays and whether you’re there for work or fun!