I highly recommend Elvia's apartment for the following reasons:
1. Location: I spent three months in Mexico City and lived in three different neighborhoods. This was by far the best--central and convenient to everything, shady and well-cared for area, plenty of food choices
2. Internet speed: excellent in all ways (ping, upload, and download)
3. Aesthetics: beautiful, light-filled space; quiet (apartment shares no walls with neighbors and faces away from street);
4. Staff: Elvia was very responsive and the doormen were kind and professional (adding to feeling of safety)