We chose Julian's apartment for our stay in Mexico City because of location near great restaurants and parks! The price is great for the location. Julian and Constanza were both very prompt in their communications.
We were excited about using the roof deck, but were disappointed to find that it was full of broken boards and holes and not really usable for us.
There was also a massive construction project (digging up the entire road) right in front of the apartment that was going on for weeks that no one informed of us. It got so bad that the entrance to the apartment was blocked and required us to walk around the perimeter on precariously placed planks over large holes. I would just make sure to check that it is finished before arriving if you have any trouble walking or seeing in the dark.
Overall, I would recommend Julian's apartment if you are looking for location to great restaurants and parks and things to do. However, I would inquire about the roof deck if you intend to use it and about the construction.