This is a great show. I've seen this twice with different performers. The first time it was with MJ, Elvis, Sinatra, and Cher. They were all fantastic and my poor husband actually got picked to go on stage and do "I Got You Babe" with Cher. He was a good sport.
The second time it was young MJ, Elvis, Aretha, and Sting. Once again the performances were spot on, especially that young Michael. Of course I can personally never get enough of Michael Jackson impersonators but that's just me.
This format works well because you get a nice assortment of artists in a good span of time. So if you're not a fan of a particular artist, no worries as it won't be too long before the next one. They also only have time to perform their biggest hits so no "deep cuts" here.
I recommend you check the schedule of who is performing before hand anyway just so you know what to expect. If you only like 1 of the 4 you might be better off seeing show devoted to that individual. They usually have a nice assortment to please a variety of tastes.