Great apartment in a great location.
We stayed here as 4 friends with a bedroom each.
Air conditioning in each of the 4 rooms plus the living room area was essential during the 35C+ weather.
Extremely well located - right by Gran Via where all the shops are, and 15min walk from many of the bars & restaurants. A number of metro stations walking distance too.
Getting the metro to the apartment from the airport also very easy (get the number 8 and number 10 trains).
Fantastic communication throughout.
Music can be heard from the club next door - wasn't that much of an issue for us but might be the others if you're expecting quiet/silence in the evening.
Highly recommended overall!