A prime location that it is easy to walk to the whole of the centre from. The downside of being so central is that it's very noisy at night. We could also hear everything in the neighbouring flat and they were very noisy from 1am to around 3am. The bed was also not the most comfortable. As a result we didn't sleep brilliantly. However, this is a very good price to be so centrally located and we thought it was a great base for Porto exploration.
As a side note, the hosts were extremely responsive to communication and couldn't have been more helpful throughout. We highly recommend them.