I stayed there with another friend last November, it is cozy and in a nice place of town, really close to everything. Just steps away from the "Moneda" and many tourist attractions.
The owners are really nice, they welcome you to the apartment and bid you farewell when is time to leave. We even got a ride to the metro station since it was raining. I would definitely stay there again!
I'm sorry I took so long to write this review, but that was the last vacation I had and have been working non stop since then! Good times though~