I've seen a few Cirque Du Soleil shows already and had I not seen Zarkana before KA, I might have given KA a higher rating. So while I think KA is DEFINITELY worth seeing, it's not a show I'd recommend seeing more than once.
The overall aesthetic of KA was a mixture of Asian and Mad Max (steampunk) which was interesting and made for some visually impressive costumes and set designs. However, a lot of the martial art sword dancing, acrobatics, and aerial acts are things you could see in other CDS performances--the real star of the show is the moving stage/platform. A lot of the battle scenes, particularly the finale, that made use of the moving platform were fantastic and really made us oohing and ahhing.
But I think what Zarkana really does better than KA is to keep the transitions between sets engaging with the audience and to ensure they don't take longer than 5 minutes. With KA, oftentimes there were 2+ transitions where not a lot was happening. Ticket prices are consistently more expensive too, biasing me to favor Zarkana in the end.