Nice, modern, spacious flat in a nice neighbourhood, very helpful and friendly owners.
The air conditioning worked pretty well, so we could sleep comfortably, despite the heat wave.
The beds are comfortable too, and the rooms are large considering our american standards !
Having the AC has the other advantage that you can let the windows closed at night so not to hear the city noise, which in Barcelona is near to extreme.
Apart from the fact that the WIFI didn't work at all during our 3 night stay, I would recommend the place for its location and comfort.