Great apartment in a very cool building. High ceilings, marble floors, and super spacious. Nice roof deck with a small jacuzzi, which we actually used and enjoyed. The location is phenomenal. It is one block away from Calle Campana and Plaza del Duque, which is right in the middle of everything and a short walk to the Alcazar, the Mushrooms, or tons of other stuff.
One other cool thing about the place was that it was all automated. You enter a code to get into the building (the first time), then you have a lock box for your electronic keys which get you everywhere in the building. On check-out time, the keys deactivate and you drop them in a mailbox by the manager's office. All in all, a cool and efficient experience.
In addition, all of the staff I encountered were extremely nice and very helpful, although the more Spanish you can speak, the better.
Would definitely stay there again :-)