The apartment is well located just a few minutes walk from Sao Bento station and the cathedral. There are some shops next door which close late, so handy for buying essentials if you arrive late. It was spotlessly clean, comfortable and quiet, and bigger than it looks in the pictures. We didn't use the garden because of the weather, but its looks like a nice to spot to sit out in, in the evenings.
Its very well located for sightseeing and getting around Porto. We took the train from Sao Bento to Guimaraes which I would recommend for a day out.
We would recommend this apartment and Porto, and hope to return one day.