Each and every waiter, front desk person, bell person, pool server, and maid who helped us at El Cid El Moro, Castilla, and Granada was absolutely fantastic. (We stayed at El Moro but got the all-inclusive so we experienced several El Cid resorts.) I can almost guarantee you'll go home and be disappointed with the service in your hometown after experiencing El Cid. The outdoor, oceanfront view from La Concha restaurant was unbeatable, the buffet breakfast there was unbelievably good, and the quesadilla bar at La Cascada is definitely worth a visit.
Advice: DO go to the 90-minute timeshare presentation to get a discount on all-inclusive! It costs about $89/day per person, but we got it for about $38 USD which is worthwhile for drinks alone. DO budget for tips, even if you do all-inclusive, and especially if you tip based on service because it's always excellent. DO try as many restaurants as you can with the all-inclusive. DO take the city tour through Pronatours (office located within El Cid resorts), because getting commentary from an actual Mexican resident makes it a worthwhile experience. DON'T expect to catch a buzz from poolside drinks, as they're very weak (but extremely tasty...try the Chaba Colada!) DON'T go to the "guest participation" night at the Pergola if you don't speak Spanish. There's some English, but not enough to make it worthwhile.
I was shocked to see that anyone said this place wasn't clean. We saw people polishing elevator doors, sweeping around the pool, picking up garbage at the beach, and the maids practically begged us to clean our rooms if we ever left and kept the do not disturb sign up. Everywhere you looked, someone was cleaning, so the effort is definitely being made.
I hope we can return again someday!