ShowStoppers targets an older crowd. Look, I love musicals and I've seen dozens but the "show stopper" tunes that were selected for this production are from old-school shows like Chicago, Caberet, Annie Get Your Gun. Don't expect to see songs from Wicked, The Book of Mormon, Lion King, or any contemporary musicals.
We had just arrived in Las Vegas an hour before the show and I was going to use this as an opportunity to nap (the tickets were "free" in the hotel package I booked). The theater was really high tech - great lighting, fancy curtains (seriously check these out), and beautiful sets. All of the performers were extremely talented and kept me awake during the entire show. My favorite performance was You're the One that I Want from Grease.
The lead female singer has an incredible voice and stage presence. She was the Show Stopper!
That said, if you're in Las Vegas, there are much more interesting shows you can see. I'd recommend Le Reve at the adjacent Wynn Theater if you haven't seen that yet.