We had a great stay in Rui and Patricia's apartment.
It's a short uphill walk from Sao Bento train station, close to all the action in downtown Porto. Rui met us at the door and showed us what was what. He was friendly and helpful. We got lots of tips for good restaurants etc.
The apartment was spacious and sparkling clean. The workmen next door made quite a lot of noise in the morning but this did not bother us too much and is obviously a temporary thing.
I would for sure recommend this apartment to others and would stay here again if I was to return to this delighful city.