This is an incredibly unique experience, and not to be missed if you want a comfortable central stay in a really cool setting. I didn't get to meet Sarah and Simon which would have made the experience even better, but they were easy to reach anytime needed and very friendly.
The boat has plenty of space for 4, and as we were just 2 we ended up each with our own "wing". It has it's quirks, after all it is a boat and moored close to lots of nature, so one needs to be aware and comfortable with that. The boat is on a secluded and private path, but people come & go on the other side of the canal, so it's not 100% private (you can hear and see them sometimes, especially in the evening when some people linger).
That said, it is super comfy, with pretty much anything you can think of, very safe, and again, a unique experience. We saw a number of wild life, while also being close to everything London has to offer.