It's definitely worth noting that other (2, I think) rooms in the house may also have Airbnb guests. It didn't cause any problems for me in practice, but it's good to know what you're signing up for, and I could see it being a concern for others.
With that out of the way, the house is beautiful and on a lovely, quiet street a short walk from Stockwell Station. The room I stayed in was clean, spacious and bright. The bathroom was clean – as noted on the listing, you'll be sharing with two others (Airbnb guests). The house in general is bright and well kitted out. In particular, it was nice to be able to do a load of washing :)
James was a friendly host, accommodating my arrival time and showing me around.