The apartment is very stylish and is really very centrally located (5 minutes from the main train station, everything in the city center is within walking distance - the new Munch Museum and the National Theater are both within easy walking distance in 10 minutes, a tram stop is practically in front of the door ).
Sometimes, however, one would wish that more attention had been paid to practical furnishings - and less to stylish decoration (for example: storage surfaces, boxes, cupboards, shelves). So you have to sort of live out of your suitcase, which clouds the overall experience a bit.
I can't judge how noisy the inner courtyard with its restaurants is in summer - when we visited Oslo, the restaurants were all closed.
Just as an aside: The "second bedroom" is actually a joke. We didn't need it, but I can't imagine that you would get permission to use it anywhere else.
Apart from that: highly recommended!