Our family of 4 (2 adults, 2 kids < 5) stayed here for 2 days in May.
Pros: The apartment was clean and well apportioned, and reflective of the photos in the posting. It is in a great location very close to the Se church at the top of a mini-hill and within walking distance of a ton of restaurants, shops and attractions. The host kindly provided a pack n' play, which was set up when we arrived. Excellent communication and the check-in was seamless - they WhatsApp you a code shortly before your arrival - one opens the front door and the other opens a lockbox with your house key. We loved how we could open the very tall windows to let in sunlight and fresh air. They kindly stored our bags for us in their office, which is just a 2 minute walk down the road. We were relying on the free (but not guaranteed) street parking in front of the apartment complex - when we arrived around 3, there was no parking, but when we returned in the evening, there were a few spots, so we were able to park our car in that spot for the duration of our stay.
Cons: Nothing major, but these were the cons: no bowls; water damage along the bathroom entry (although they noted that was the result of the last tenant in the apartment above and that they were going to fix it immediately upon our departure, so that shouldn't be an issue any longer); a few homeless people in the vicinity.
Overall, it was a great stay and I would recommend this home for anyone staying in Porto.