One of the more enjoyable places that I visit is the Hard Rock Cafe'. My wife and I usually go to this spot at least twice on each of our visits to Cancun.
I find that the most enjoyable time to visit here is from 9:00 pm and later. Two live bands perform on most nights at 10:30 (all except Wednesdays). The music that they play ranges from Selena to U2 to Lynyrd Skynyrd. The bands that I have seen have been high quality cover bands.
The food is traditional for a pub; burgers and fries, salads, sandwiches, and chicken wings. The drinks tend to be watered down. But, the atmosphere and the music make for an exciting evening.