This is my first time seeing Ka by Cirque, and it was a fantastic experience. I was able to get seats in one of the front sections, about 10 rows back on a Saturday evening. I'm actually a bit surprised, but the theatre appeared to be about half empty.
Anyway, the show was awesome. I really enjoy Cirque shows. In the past, I have seen Mystere and Totem (not in Vegas). Every Cirque show is different, and it is unfair to compare them, because they are so different and unique. Ka has an amazing theatre at the MGM Grand, and the show has some dark parts and some happy moments.
The acrobatics, effects, and acts will amaze you. I really don't think there is much else to share, because you should experience it for yourself.
Cirque is one of those shows, that I feel bad about spending $150 or more per ticket when I purchase it; however, after the show, I totally forget about the money and realize it was 100% worth it.