I was in the appartment for 2 weeks for business trip and i found everything i need into it and outside as well. All convenient stores and restaurants are no more than 300 meters away. I was lucky enough even finding a bus so close to go to the office ;P
There are also some nice park to relax.
Anyway i also enjoy walking and 15 min from Nationaltheater Metro was pretty close ... and here you are really downtown.
Well i strongly recommend and will appreciate going back for my future travel to Oslo.
Andreas was away when i arrived but his sister greatly welcomed me. Both of them were promptly reactive to my small ''texting'' request.