I've done Airbnb a lot of times before and this is the best apartment that I've stayed in Buenos Aires.
The apartment is great, with a lot of space, beds are very comfortable and bedrooms are very quiet.
The location is awesome, lots of good restaurants nearby where you can go to by walk.
Roberto is a great host, he was very flexible with the check in and the check out time.
Do not hesitate on booking this apartment, you will thank me later.