Very secure, spacious, and comfortable apartment. Worked out well for the two of us. Comfortable living room, well equipped kitchen, good bed and bedroom has storage for clothes. Narrow balcony running the width of the apartment where you can leave the doors open to let in the breeze.
A few restaurants and groceries close by. Not a far walk to the heart of the city. Multiple bus stops very close by for getting around.
A little noise at night with the balcony doors open as there is a residential street below.
If you are not sure about visiting Porto, just do it, you won't be disappointed. Plenty to do and see and a really good vibe.