We had a short stay at Alejandro's place and we really enjoyed it. The apartment is located in a quiet place, just few minutes walk from the metro, has an easy connection with the airport and the bus station. And for those who prefer to walk... it's only about 20-30 min away from the center of Madrid (walking). We were 1st time in Madrid and came just for 2 days, but with nice recommendations from Alejandro we have seen the most interesting sights :)
Big plus. The room and the apartment and the building were very clean.