The location is excellent. A calm and safe neighborhood with walking distance to the charming Raval, Gotico and Born on one side and Gracia on the other.
The apartment is well planned, but be aware of that it’s all open space, I.e. there is no door til the bedroom. If you are many the warm water runs out quite quickly.
The agency did react quickly on my requests, but were not very present during my stay of 3 months. We where only in contact when I contacted them.
Overall a very good place. And I would recommend it for your stay in Barcelona.