A very nice, recently renovated apartment. The location is very good, a 20ish minute walk to town or shorter by metro. The Augarten park is also very close. The loft bed is probably nice if you have kids, but I was traveling alone. The kitchen was sufficiently well equipped that I could cook basic meals during my long stay. Overall I recommend Zheng Juan's flat.
Some concerns: The main bed is two mattresses put together with a large gap where the mattress have weakened between them. The blankets/comforters are small and so aren't great for larger people. The apartment is also poorly insulated against sound. This is generally not a problem as it is a quiet community, but during waking hours you can hear the noise from other tenants of the building and in the morning the people rolling the garbage bins. Also when I booked it was written that AC was included in the flat, there is no AC. Airbnb does not send you a receipt with these details of the reservation so when you check again later if things like AC are removed you have no proof. I recommend taking a screenshot at the time of booking. (I am certain I booked with AC as it was the number one thing I was looking for in my booking knowing Vienna is hot in the summer)