Sophie's flat is very well situated. Bus stop and tube station are close by and the neighbourhood is relatively safe.
Sophie was very nice and easygoing and replied to messages very quickly. However, I was not aware that she is not actually living in the flat, so expect to share the space with a second guest who rents the other room. This was not indicated in the listing and I would have liked to know beforehand. Due to this, the flat is a bit cluttered, as Sophie still keeps her stuff at the place, added to by your and the other guest's stuff.
The upstairs neighbours are a bit noisy and the ceilings are very thin, so unfortunately you can hear every step they take, but earplugs saved my sleep. Mattress not for people with back problems.
Nevertheless, I enjoyed my stay in London and at Sophie's flat, even though it wasn't the best pick for me.