I stayed at Ariana's place for 6 nights. First of all we absolutely loved the location. For any first time visitors to the city I would recommend this area. It has lovely feel with some beautiful 1920s art deco Mexican architecture and tree-lined streets. We enjoyed walking around the neighbourhood including the nearby restaurant district which had many options. The metro station is around 10 mins walk away and we felt very safe even late at night (we were two female travellers). Within two blocks there is also a great cafe with delicious coffee and breakfasts. Across the road is a convenience store which I think is open 24/7, if not it has long opening hours!
The flat itself has a great layout and the beds were very comfortable. Good wifi connection, use of the television, and very responsive communication from Arianna including useful advice on taxis. The place is also very clean. For us visiting in December we found it a little cold inside the apartment and there is not much natural sunlight. The shower is also quite temperamental and not easy to regulate the temperature.
Overall we enjoyed our stay, it was a great base to visit the city - I just wish we had stayed a little longer!