We were just there last month and stayed at the Grand Mayan. The resort is huge and a lot of walking is involved. Paths and buildings are not very clearly marked and it took a day or two to get acclimated. There are shuttles that run every 15+ minutes or so to get between areas, but sometimes the wait is longer. The pools are gorgeous and well-maintained. Happy hour is from 12-4 each day, 2 for 1 drinks. Ran about $8 for two, have to be the same kind.
From what I understand, the Grand Mayan is an upgrade from the Mayan Palace. Our room was very comfortable and included the plunge pool. Kitchen supplies were a little less than usual. We ended up doing room service and going out for dinner instead of trying to cook dinner in because of that. We found the prices not bad at all after the exchange and did shop at the deli/grocery on site. The breakfast buffet at Del Lago was unbelievable and ran about $20/pp. The beds were comfortable and the room was serviced twice daily. There is a $75 "resort fee" which includes wireless internet for 3 devices. Overall it was pretty reliable.
The resort has a shuttle to Playa del Carmen and it costs $6/pp one way. It drops you off near the Wal-Mart or Mega stores if you want to go to town to get groceries. I believe it ran at 9,11,1, and 3 going into town and the return trips were at 12,2,4 and 6. It also drops you off right downtown if you'd like to just shop the touristy area.
The resort does offer transportation from the airport to the resort for free. You need to contact the concierge in order to arrange this. We arranged for the return airport transportation through the Grand Mayan and it was $15/pp.
We did go to the Cirque du Soleil show while there and, although not quite up to Las Vegas standards, it was very entertaining.
One word of advice - BUG SPRAY. You are in a "jungle" and the mosquitoes had a heyday with all four of us.
Our son was there playing in the PGA event while we were there and was staying at the Grand Luxxe in a 2 BR. All I can say is I will definitely try to get into there the next time -- it was absolutely gorgeous!!!
Enjoy!