I stayed with my girlfriend for 3 nights and it was what we expected. The host was very nice, she waited for us to check in even though we were arriving quite late. The place is clean. It doesn't have many extras, but all the basics are covered and you can't ask for more for the price. The house is a little bit far from the center, but London transport system is very good so it's not an issue at all. Within 5 to 10 minutes walking there's a Southern line train station connecting with Victoria, and buses are a good option too (Line 250 to Brixton, it works all day, even late at night).
I'd stay with Aszet again if I'm ever back in London.