Eirik is an extremely helpful, generous host. He has well deserving of his superhost status. His apartment is in a great location, is comfortable, has strong wifi, and you'll have everything you need within easy walking distance. I stayed for four weeks, and would definitely stay at his place again. The water, Munch Museum, opera house, and main train station are all about a 10-15 minute walk. The area is safe, but if you arrive after dusk I recommend approaching the apartment from the south (use the main pedestrian bridge over the train tracks) if you want to avoid vendors of illicit substances on the north side of the train station and on Gronland. They won't hurt you, but they're annoying. Enjoy your stay in Oslo!