Positives; appartment is walking distance to the historic centre, a large supermarket and restaurants. I wouldn't say it was my favourite area, there was more going on in Massarelos, but it is cheaper to stay in Bonfirm and still walking distance to the busier places. The appartment was clean when we arrived and check-in was easy.
Negatives; the space is cramped and not having a sofa to relax on was really annoying when staying for 2 weeks. Cleaning supplies weren't supplied (we bought our own) and the quote for a cleaner to come seemed much too high.
I would recommend this place if you're staying in Porto for under a week, but would get somewhere more comfortable if staying longer.