All I can say is that this show is absolutely breath-taking, figuratively and at one point quite literally. Having had a backstage tour, I know of some of the secrets to the magic of the production, but even having seen the shows mechanics, it is still quite hard to believe the show is real.
Let's take for example the theatre's blue and green ceiling. It looks like it was designed to mimic the lobby of the hotel, but in fact it's lighting hitting dusty chicken wire. Turn those lights off, and it's amazing to see the difference.
As for the stage itself, it's a 25-feet deep, 1.5 million gallon pool of water. The first row is surface level, so you don't see anything underwater. The pool has 7 hydraulic lifts (I think it was 7) that can rise to the surface without causing the slightest wake on the surface. This is done by thousands of tiny hand-drilled holes placed systematically through the stage platform.
You'll notice that part of the theme of O is opposites. Within a matter of seconds the stage backdrop will go from black to white and vice-versa. The same is said with the stage which at one moment is a pool 25 feet deep to within a matter of moments being completely dry land, all without a simple wake. Other times some of the platforms are mere centimeters below the surface, making it appear as if the performers are walking on water.
I do love Cirque's touring shows, but there are obvious advantages to resident shows. For instance, you can't transport a stage as elaborate as O's. Not only does this allow for more technically amazing feats, but makes the show seem that more ethereal.
If you have seen other Cirque shows but have yet to see O, it's worth it. Absolutely worth it. Actually, if you haven't seen Cirque, this would be a great one to see. It isn't as energetic as Ovo for instance, but it is certainly magical.