What a fun stay on a houseboat! My family (two kids ages 9 and 11) had fantastic weather most of our trip, so sitting on top of the boat with a beer watching the tourist boats go by in the center of the city was as idyllic as you can get. I was impressed that we hardly felt any rocking at all, especially given how many boats went by during the day.
We loved the location - easily walkable to restaurants, shops, bike rentals, Metro and the flower market. One recommendation - don't take a car from Centraal station if you're coming in by train. The Metro (or walking if you pack light) would have been much faster.
Friday and Saturday nights were a bit noisy with late night clubs across the canal, but we were so tired from the day that it didn't bother us. The beds being comfortable helped too, and Daan had extra blankets and pillows stocked that we tapped into.
Daan has a bunch of DVDs stocked which made for a good way to unwind from a busy day sightseeing. The other reviews about the surprising roominess of the boat held true for us, and I appreciated that the two bedrooms were on opposite ends of the boat.
All-in-all, Daan's accommodations and hospitality made for a great first trip to Amsterdam.