Very nice place, modern, good accommodated, all you need is present. We only met Maria, who is a perfect host.
It's a bit further away from the historical center, but if you don't have trouble to walk, I would recommend to stay here due to the fact it's very quiet, has a metro station nearby (at least 4 lines come together), near Casa da Musica,...
You don't feel like you're renting a part of an appartment where the owners live; all is perfectly separated due to the distribution.