Our stay at the flat was exactly what wanted - a private apartment in the centre of town, superbly located right by the São Bento station, that would allow us to nip in and out on our exploration around the city. The place was clean and very modern with everything we needed (including coffee, a tin of biscuits and a few beers which was a nice touch!) The best feature of the whole place was by far the shower; having 3 separate settings and very powerful, you'd be pushed to find anything of the sort in a five star.
I would say 2 points to consider of this place (which aren't necessarily negative) is that one; there's very little natural light, with just the front door and a skylight in the back, it can be a little cavernous. Personally I don't see this as a problem, but if you're wanting a spot with a view then this maybe isn't for you. Second is that Graciete and João were brilliant with communication, replying to any messages and questions we had, however; we didn't meet anybody! So if you're looking to come to Porto and have the personal airbnb host showing you in etc then, again this may not be for you. Once again for us this wasn't an issue, as enough information was provided in the flat and any questions were swiftly answered over chat.
Lastly I'd say after seeing people complain about the fact a soup kitchen was located across the street, any future guests should not factor this in. It really was not an issue. People lined up in the early evening nearby, which did get a little rowdy, but they didn't bother us in anyway, were in the building and then gone by the time we were back and off to bed so the street was very quiet. Unless you're planning to go to bed at 7 (in which case what are you doing in Porto!?) then don't hesitate to book this place.
Overall, tip top.