I can highly recommend the airbnb. The location is outstanding and you’re directly in the Centre of the historic town. Basically everything can be reached within 5-10minutes walking distance. There are plenty of highly recommendable restaurants super close such as NOLA kitchen, Muu Steakhouse and Chama Restaurant.
The Appartment itself is cozy and provides you with everything you need. I’d say it’s a perfect base if you stay a couple of days here in Porto.