My husband and I absolutely loved staying on Simon's houseboat. Staying in such a well designed and beautiful place where we could relax and watch canal life go by was a highlight of our two week trip to Europe.
It was easy to coordinate check-in/out with Simon - he was very responsive. The place is brand-new and very clean. We even got coffee capsules and two ciders to enjoy during our stay.
There are a few things to consider - one is that the kitchen is best for light breakfasts/coffee. There is a fridge, microwave, and small coffee maker. This worked out well for us though because there are so many restaurants near by to check out that we didn't feel like cooking. The shower is also not separate from the rest of the bathroom, but we had a squeegee and even in winter things dried out quickly.
Speaking of winter, between the main heater and space heater left for us, the space was plenty warm. We thought a houseboat in winter may be a bit cold, but we had no problems with this.
Bottom line, this is a very special place to stay and I would highly recommend it as a unique, relaxing experience.