We were in Madrid for 5 days, and we had a wonderful time staying in this apartment. Its location is the best; it is in the centre of the city, so we didn't have to use the public transport, most of the sights were in walking distance.
The aparment is well-equipped and we got what we have expected from the descriptions and picutres. The only downside of the apartment was the sometimes smelly bathroom (probably its because of the building).
And last but not least, de hosts were the kindest, we got restaurant and taxi (for the airport) recommendations, and they always answered our questions fast and kindly.