John and Tom were excellent hosts, friendly and welcoming, even though my flight didn't get in until midnight. I enjoyed getting to know both of them. Their apartment is comfortable, clean, and roomy. The room is on the small side, but it is certainly more than big enough for a single guest. They have a very friendly cat who liked to come visit me. The location is ideal, just a few blocks from the train station, a block off Karl Johans Gate (the main pedestrian-only shopping and restaurant street), and an easy walk to the Opera House and Aker Brygge, the area on the marina where there are lots of great eateries and lots of nighttime activity. I'd definitely recommend staying with them.
The one negative is that there is currently construction going on in the neighborhood. Some days it started very early or continued very late, (one night past midnight) , even on the weekend when I was there. It might be good to check with John and Tom to see what the current status of the construction is.