Felix's place is very spacious, clean and tidy. It's got some nice little cafes around and is convenient for both Retiro Park and the metro for getting around.
The one issue we had is that the front door is extremely difficult to open. My friend at one point was unable to gain entry, however, Felix did kindly come and assist.
There was also unfortunately loud building work being done in the apartment block during our stay.
Overall however a good value for money stay in a good location.