I had work to do in Porto and the place from Sílvia and Ricardo was just perfect :)
Everything i needed: a great apartment close to the center but still not too full, great kitchen, bathroom and bedrooms.
You are often able to just walk if you need something to eat etc.
I even suggest to do so as Porto is a beautiful city. Just go up north for about 5 minutes from Sílvia and Ricardos place to the first bridge and you'll see :)