The place is very good, especially the bedroom and the bathroom, both are very nice. It was also nice to have a big, nice TV in front of the couch (not usual in Madrid, for some reason), and all the appliances worked great.
One downside is that the place is very dark, there is a window in the living room and a very small one in the bedroom, both leading to an inside patio, but almost no light comes through because the glass is fogged, and in the winter you don't want to open those windows anyways. So, I spent a whole month with no outside light. Also, the couch (which probably transforms into a bed) is very uncomfortable.
All in all, it is a very nice apartment. As I mentioned, the bedroom and bathroom are top notch, and it was clean and comfortable. The only two downsides are the couch and the lack of outside light.