I enjoyed my stay (2months !) at Sara's place. The flat is well located : the area is fine, very close the several underground stations. The flat is cosy and everything is provided to have a comfortable long stay : furnitures, TV, cable, internet, Netflix, Washing machine,...
The WiFi could be stronger for the price I've paid : It was not working well in the bedroom and sometimes even not in the kitchen.
I would also have appreciated a better communication from Sara. I absolutely didn't understood that she was actually not living in the flat anymore and had then no idea with whom I was going to live with. My two flatmates neither, and didn't knew anything about me before I arrived : why I was coming, for how long and when I was suppose to arrive. It was akward and uncomfortable for us all.
Anyway, all in all, my stay was fine. But maybe (with the AirBNB fees) a bit too expensive.