This was a fabulous find, and perfect for two of us to explore the city. Very centrally located right opposite Sao Bento station, and with bus stops and metro right outside the door (be a little careful with the bus routes, as some are altered for the next few years and don't necessarily go where you think they go!).
The apartment has everything we needed for a week stay and was very comfortable. Personally I found the bed a little firm, but beds are a very personal preference anyway. It was pretty cold while we were there but the supplied heater was more than enough to keep the place cosy. Would certainly stay again when we are back in Porto.