We stayed the week of July 10-17 and were the last flight out of the airport before Emily hit.
In reading the following, consider the fact that I am a very picky traveler and have been to some extremely nice locations and properties in the past.
Pros: Fantastic location. Great views. Good balconies. Nice to be able to walk to restaurants, shops, bars, mall, flea market, etc. Beach was very nice and water was calm as advertized. Rooms were pleasant (we had seven of them), and had nice little balconies, sitting areas and views. Not all views are directly of the ocean. The resort has some wings which angle at 25-30 degrees so some rooms at either end are mostly looking over the pools and back toward the main portion of the hotel. Better rooms are in the center. Rooms are quiet but loud noise in hallways (if present -- provided by your fellow guests) is disruptive.
Cons: As mentioned by some others, beds were quite firm. Not a problem for me but my wife and others in our group did not like them. Towels were rough, and not what one expects in a luxe resort. AC fan was loud (although user-controllable) and needed to be on all the time to keep heat/humidity under control. Food was OK and resort expensive. Housekeeping schedule was erratic, and we could not count on the room being cleaned before 5 even if we were gone all day.
Jet Ski rental seemed reasonable ($55 for an hour) by comparison to some other activities. Teenagers enjoyed the experience. Segway tour ($40 for an hour) sounded like a good value and something different. Pool was warmer than my taste and shade was not always easy to obtain, although we seemed to manage OK during the week.
I used the indoor tennis courts once. The cost was $22 for an hour. The surface is astroturf in sand on concrete. It was a good, forgiving surface. The light is fine and it is cooler than playing outside, but it was still plenty hot. Three courts with netting between courts.
There was one patch of coral in the beach swimming area which had some decent sea life (fish, urchins, baby ray, etc.). Concierge and counter staff were helpful, but not wonderful. I think I would prefer the Ritz if it were as well located and well priced. FA Grand Aqua is in a good spot, across from La Isla Mall, and looks nice on the outside. An earlier reviewer moved to this hotel and liked it better than FAGCB. Cab drivers told me three top hotels were Ritz, JWMarriott and FAGCB, simply reflecting the five-star ratings of the three.
Diving with Manta Divers was convenient, as they are just up the road from the hotel. Reefs I saw were not as dramatic or as full of life as those I have visited in Grand Cayman, but still good. Visibilty was good and a wetsuit is not essential. Owners of Manta are nice US folks and put together trips to Cozumel and other dive sites, too. They were easy to work with, including online before we got there. Time on boat to get to dives was minimal, much better than other operators, I think. Manta has a website.
Taxi to La Habicheula restaurant in old Cancun/downtown Cancun was easy and reasonable, and the restaurant was quite nice and modest in cost compared to the hotel food. Juan Carlos Conde Reyes, van driver (---) is a good option for a group. He speaks and understands English well and his van fit our group of 13.
Breakfast buffet at Igwana Wana at next door mall is reasonable and good. It starts at 9, though, which was a little late for us. Mall opens at 10. Indoor "Flea Market" just around the corner from the hotel is an interesting place to get things cheap if you don't mind getting a lot of people calling out to you (Hey, Senior, want to buy...). One feels like chum in the water if one stands in one place for long.... 100% Natural restaurant, now located across from Senior Frog's, was good and reasonable and an easy walk from the hotel.
Zipline/bike/cenote experience at Selvatica was good and included transportation from hotel for $60 (cash or Traveler's Checks only). It was hot but fun. One hour's drive, including a 19k stretch on a bumpy dirt road. Includes H2O and a nice, light lunch. They have lockers for your free use. Google Selvatica or Selvatura for details. Tree tops are not 100s of feet up, only 30, I would guess. Fun but not terrifying. Something different to do. We left at 8 and got back at 2 or 3. Reservations a must. They have a website.
Our weather was sunny and hot throughout our stay. Some local (walking distance) restaurants do not have AC, but are open air both inside and out. Beer, wine and snacks are around the corner at a couple of stores. There are many pharmacies in the area which all sell prescription medications over the counter. Crossing the street is not for the faint of heart in many places. Once committed, I recommend you be quick in getting to the other side.
This is a very nice hotel in a great location. If you want waves on the ocean, it is not for you. If you want to walk the beach, this is not for you. If you want ultimate luxury, you may prefer the Ritz (although I have not seen the inside of the Cancun Ritz), but you will need a car or a cab to get to things like restaurants and stores. One of my sisters was in the hotel when Emily hit (in the ballroom). They did not lose power and I don't think they sustained major damage.
I had good cell phone coverage in Cancun and at this hotel. My Blackberry worked well and was an essential tool in dealing with hurricane travel. Consider activating your international roaming for the data service. T-Mobile's rate while there for voice is $1.49 per minute.
I am happy to answer questions if I can.