The flat location is very close to the historic center of the city, all the main places of interests are nearby.
The view from the window is the killer feature of the place, this is why we rent it, there are people coming to spend an evening at the mirador nearby.
What we didn't like much were the wooden stairs and the floors, and weak general soundproof in the building, but these seem to be the disadvantages of most of the old-fashioned traditional portugese buildings, and it wasn't a problem for us at all.
Also there is a supermarket close to the flat that has fresh seafood every day - pingo doce.
All in all, it was a wonderful stay, we definitely recommend and we'd like to stay there if we come back to Porto.