My girlfriend and I stayed for just over a month and absolutely loved it. We were attracted to the rooftop, which was great, but in the end our favorite aspects were the location and the quietness (with exception of a couple odd nights where neighbors partied), which we learned is not common in Mexico City apartments (often there is road noise early in the morning).
Wifi is very fast. The king bed is firm but comfortable. The shades in the bedroom are blackout. There is a great amount of natural light and airflow - I loved the routine of waking up and opening the shades/windows. The school next door didn’t seem to be in session.
Karen is very responsive, although we didn’t need to contact her often.
The only weak point I’d mention is that the couch/futon isn’t very comfortable. This wasn’t a huge deal for us but worth mentioning for anyone who plans to work in the apartment. We had friends sleep on it who thought it was comfortable as a bed.
The kitchen was completely usable and had what we needed. The whole place was easy to clean and easy to live in.
If you’re looking for a launch pad to explore CDMX, I’d highly recommend this spot. Cafe NiN is right next door, which was a huge plus.