The real star of "KA" is its stage. Cirque cleverly disguises this before the show, but I won't say anymore here as to not spoil it for you. Still, the stage is AH-MAY-ZING!
More story driven than the other Cirque shows--though that's still not saying much--"KA" is an homage to tales of the ancient Orient. You have good vs evil, love (both familial and not), and again, that amazing stage.
If the acrobatics are what draws you to Cirque shows, you may be disappointed. If you want to be entertained, you'll be just fine.