I had a day layover in Mexico City prior to flying to Acapulco. I found a fairly decent rate at the Sheraton Maria Isabella and booked it. This was my first time in Mexico City, and I was unfamiliar with what part of the city to stay in.
I arrived very late and had some trouble with my baggage at the airport. I took the "recommended" taxi service (probably a rip-off, but I didn't want a hassle.) The ride from the airport was around $25.
As for the hotel, it has a fairly nice interior in the lobby, but they were doing some construction while I was there, so I would expect it to be improving.
The room was very elegant for the price (I was given a tower room.) A very helpful and friendly bellman took me to my room and spent quite a while making sure everything was how I wanted. After tipping him, I called for a wake-up call for the next morning. When I picked up the phone, the floor's butler asked when I would like to get up. The next morning, he arrived to wake me up, but he brought several types of juices, coffees, teas, and breakfast rolls. He also laid out several different newspapers and got the bathroom ready (laid out the robe, brought hot towels, etc.). All this for $90 a night!
I left that morning to take a quick walk around the area, which included the Chapultepec Castle and Park (Zoo), Xochimilco Floating Gardens, the Museum of Anthropology, the Rufino Tamayo Museum, and Basilica De Guadalupe. It was a great day.