Whenever someone tells me they're going to Las Vegas, I always recommend them to see O, if there is one show you see, it should be this one.
As far as I know O never has discounts and is always sold out so book early, seating is $150 and that can range from up close to far back, so you may as well book early instead of waiting till you get to LV.
The stories are interesting enough but the stunts literally make your heart drop.