I echo all the other reviews - great location that leaves you very close to top neighborhoods (Roma, Condesa) in Mexico City and the accompanying restaurants, cafes, etc.
Rosalia was very responsive. The studio was very clean (I'll even note some of the nice touches like the quality of the bed sheets), and indeed it offered peace and quiet, which can be rare in Mexico City. Getting in and out of the building (a security guard buzzes you in) was a breeze.
One major weakness was the lack of air conditioning. Apparently a lot of buildings in the city lack AC, but I was surprised given this was relatively new construction. If it's on the cooler side in Mexico City, won't be a problem.
But if you're feeling sick like I was, and do not sleep well in a very warm place, this was very difficult. The apartment was on the 7th floor so naturally it was very warm to begin with.
They have bad-ass blackout curtains that help block out the morning sun and it's warmth, but the windows only open slightly, and there was only a small fan provided.
So if you're sensitive to heat, consider an alternative; otherwise I was very impressed with the unit and the experience.