Not the cheapest ticket in town but who goes to Vegas to save money? Live a little. Splurging on this show wont be a regretful experience as this is far and away the best Cirque show on the strip.
The actors/acrobats were nothing short of amazing. The things these people were able to train their bodies to do is awesome in the truest sense of the word. High flying, breath-taking and visually hypnotic, "O" is an experience you wont soon forget. Just as impressive, to me, was the stage for the show. This thing must have cost a fortune the likes of which NASA would have trouble calculating. The stage alters between pool, runway, stage, river, ocean and vortex. It switches between modes so seamlessly that I found myself marginally worried at times that somebody forget to hit a switch somewhere and one of the actors would dive into the hard stage instead of a pool.
I was visually and aurally impressed for 90 straight minutes. When in Vegas, this is a must, if only once in your life.