We had a wonderful time and it was truly a unique experience. We were looking for something in an area of London not overwhelmed with tourists and this was definitely that – only a short walk from Islington, with lots of shops and restaurants without a ton of people. We also enjoyed walking along the canal to Granery Square, a huge complex of shops and restaurants, and transportation to pretty much anywhere you need (Kings Cross station). The house boat itself was quite private, definitely was nice to be on the private side of the canal (vs the public side where people seemed to hang around quite late).
Sarah and Simon weren't able to meet us when we got there because they were away, so we didn't get a lot of information on the area or how to work things on the boat, but we figured it all out through a bunch of reading material left for us.
Our biggest disappointment was the heating situation. I sent a message prior to booking explaining we had an infant and wanted to make sure it would be warm enough for her. We were assured it is quite warm and cozy with the central heating, space heaters, and wood burning stove. When we arrived, the central heating wasn't working – it apparently had stopped working a week before we arrived. I really wish this had been communicated to us before we got there, knowing heating was a primary concern for us with the baby. The space heaters did the job, but if you ran more than a couple, it would trip the fuse and you had to go outside to reset it. Even keeping them on throughout the night (which I didn't feel great about) our daughter's had ice cold hands in the morning (we couldn't wrap her in a blanket because of her age). We used the wood burning stove 2 of the nights, but this is really only an option when we planned on staying in for the evening... and while it does warm up the cabin (and is quite nice and romantic) there's a fair amount of smoke in the cabin which concerned us a bit with our daughter's tiny little lungs. Plus, it only really kept it warm for the first part of the night.
That all said, there were a couple of other small issues during our stay and Simon and Sarah were always responsive... they just didn't go above and beyond to make sure we were comfortable (specifically with the heating, would have been nice to check in on us after the first night knowing the issue about the heat).
If you don't have a baby and are looking for a unique way to experience London, I definitely recommend! Just know/realize, at the end of the day you're staying on a boat. :)