We stayed for 4 nights at Adriano and Raquel's place. We were searching a flat for 7 person in Porto and didn't expect so much in general. But the flat was beyond our expectation and it was very comfortable for all of us.
The flat was very beautiful and clean. Although we didn't plan to spend so much time in the flat, we spent evenings in the flat, just to enjoy terrace with good weather.
If you are big group and looking for a Airbnb in Porto, I can only recommend Adriano's flat.