The photos of Penelope's apartment speak for themselves: A stylish, picturesque flat in a stylish, picturesque home in the stylish, picturesque La Condesa district of Mexico City. All at an unbelievable value, to boot.
Being that this is a historical home, there are some inevitable downfalls, namely poor insulation. This not only results in it being very cold at night (you'll need the extra blankets Penelope has in the room!), but very humid as well, which makes it difficult for the towels to dry. I also thought some of the furniture and furnishing could be updated, but in the grand scheme of things these are very minor issues.
If this place is available during your stay, I'd recommend it!