Out of the many acts that performed on the stage, only two were truly spectacular: Elvis and Christina Aguilara. Apparently Michael Jackson impersonators can no longer perform on the strip (when I went, but he appears to be back); the rest of the cast included Tim McGraw, Britney Spears and Rod Stewart.
For a show that is never found on the locals free ticket circuit, this theater was amazing full. I do know they give a lot of free tickets away at the hotel itself (or 2 for 1) so you can find deals to check the show out. Most all of the seating is in either a booth or table format, so if you sit at the front of the table, you will have to turn around to view the show.
The Elvis impersonator did win the best Elvis in the world competition a few years back; he's quite good. The Christina Aguilara impressionist may not have the looks of the real thing (though very close), she does have the chops.
If you can find a good deal on the show, check it out. I wouldn't take the kids (little risque with Britney and "X-tina") but couples will enjoy a night out with the "superstars" of America.