I have been guest of Serena for two months and it was a good experience. The apartment includes all the comfort for a long stay and it is located in a good area near the Sofy stadium and close to the airport (the airplanes are a bit noisy during the day, but everything can be solved closing the windows).
The only problems I encountered during my stay there, were related to the internet connection, but the host solved them immediately.
In conclusion, I will consider again this apartment in the future if there will be the possibility.