We had a great stay at the Cedofeita Art Studio! The apartment was clean, bright, and newly renovated, with very strong WiFi. It was situated in an ideal location within walking distance of many of Porto's top attractions, but just far enough removed from the tourist crowds in a more local neighborhood. We are so glad we stayed here and not in the insanely packed Ribeira district!
The only minor negative to the apartment was that all noise from the stairwell carried inside (the sound of doors closing, people talking, etc.) This didn't detract from our stay, though--there are just a handful of apartments in the building, so there isn't constant traffic in the stairwell.
Also, the hosts were excellent. They were friendly, responded quickly to messages, and even left us a bottle of wine and some chocolates as welcome gifts! We would definitely stay here again and highly recommend this place to others.