The apartment is pretty sweet: very clean, great location, check-in and checkout were made really easy too. The security guards were very friendly as well, it's standard procedure for them to check IDs at your initial check-in hence the request for photo IDs. If safety is a concern prior to visiting, this should set your mind at ease since everyone staying in the building has to do that as well. Besides, Mexico city is as safe as any other large city. One thing to note, this apartment is in a bustling nightlife area. That was no problem for us but something to note. The apartment blocks out all noise and so it's never problematic.
Carlos is an excellent host, very communicative, and made sure everything was in order. He responded promptly to all our questions, gave great suggestions, and was very easy to deal with.
100% recommend this spot, would stay here again whenever I'm back in CDMX.