I stayed at Frode's place close to 2 weeks and had a great time.
Frode is super nice (he picked me up at the tram stop!) and his place is beautiful. I was in Oslo to do some independent research for my PhD and just needed a peaceful, quiet place to stay when I was not working. Frode's place was absolutely perfect for this. The apartment is super nicely decorated too - to the extent that my boyfriend actually commented on it when I skyped him one evening.
I was a tiny bit worried about the location since there's not a T train station super close by. But this worry was pretty unfounded as there are plenty of trams and busses going to and from the area all the time. The neighborhood itself is super cute - lots of independent coffee shops and small boutiques. It's also close to Akerselven, small stream that runs through Oslo, where I'd go on runs and walks if I wanted to be in some green space.