We loved to stay in Pedro's apartment, really nice, close to the city centre (5 minutes walk), and to other useful services (metro and train station).
The decor is lovely, and Pedro and Bruna were available to reply to our questions.
We had only one problem on Saturday night with the club on the ground floor, that organized a party all over the night.. But also Pedro assured us that in the other nights it was closed, so maybe it was an exception.
We recommed to stay at Pedro's house if you want to easily walk around Porto!