Great location, very near to Porto city centre and good connections to/from the airport since the Trindade metro station is close by.
The apartment was very spacious, bright and well decorated. Furthermore, it was clean.
The only disadvantage was having to get the keys at the Welcome Center which is at a 30-minutes walking distance HOWEVER it must be said that one could opt for a check-in at the apartment for EUR 10.
Overall, it was a very pleasant experience and I would recommend staying at this apartment!