We really liked our stay in Oslo. Conmunication with John was perfect. the apartment was super clean and stylish. The biggest downside it has is that it is located just below the rooftop, which makes it super hot when temperature in Oslo is high as well. There is no AC as 27 Celsius is not a standard temperature in Norway.
When you open the window to cool the room, you will get all the noise from the city centre (but on the other hand, everything is in proximity).