We enjoyed our stay at this apartment. We were 3 couples plus a baby and there was plenty of room for all of us to feel comfortable. The location is close to a metro and the main pedestrian only shopping street. There are cafes and restaurants within a few minutes walk.
We used their transfer service from the train station and that worked well.
The views from the windows wasn’t great, but that’s not why we visited Porto.
I’d recommend this apartment and wouldn’t hesitate to stay here again.