The flat is absolutely lovely. It's got a nice terrace and it's located in a nice area of Mexico city.
Our hosts were fantastic and very accommodating.
The only problem was the combination of noise and lack of soundproofing. We could hear people washing their dishes on a flat close to ours as if they were in the same room. There's also a mechanical rumbling late in the night that could wake you up.
Other than that I fully recommend it based on the combination of location, cosiness, aesthetics and of course the wonderful hosts.