The apartment is a calm, comfortable space in the middle of Mexico City's wonderful Roma Norte neighborhood. It's the hosts home, not a rental-only space, full of books and original art, which I really appreciated: it felt like I was getting an immersive experience. Gutemberg also made me feel like I was a guest, and was very responsive and friendly, constantly recommending or inviting me to things. There were a couple of things which went wrong (the washing machine and the boiler were both problematic in the two months I was there) but in both cases, Gutemberg reacted fast to help out.
The apartment has its quirks (the floor is uneven, the microwave required some acrobatics to use), but I personally found these added to its charm. Mexico City is a city full of quirks.
The location is excellent: central and at the heart of one of the most livable areas of the city, packed with great food, cafes and culture. Transport connections are ample (two metro lines, metrobus and eco-bici)