We actually paid $110 per night for two people, which included the all-inclusive package for all meals, beverages (including cocktails and beer), and all resort activities. We found this deal through www.orbitz.com (NOTE: this is also a resort that is available through an exchange through RCI).
The resort was very nice, with a great location on the beach (most resorts in Cancun are!). The facilities were clean and well maintained, although the sleeping rooms were a bit sparse (but who goes to Cancun and just stays in the room?). The bedroom and bathroom were really fine. The activities staff -- the Fun Club -- kept things happening poolside all day from 10am until 4pm and was fun for guests of all ages.
In addition to the full buffet for breakfast, lunch, dinner, and snacks, there are three specialty restaurants (Mexican, Brazilian, and Italian), which are a la carte (dinner only) and included in the all-inclusive pricing, but require advance reservations). The buffet (breakfast, lunch, and dinner) offerings were assorted and all very good. The dinner buffets were themed and offered items for all tastes, including things kids would enjoy.