The short form is if you like the Mythbusters TV show then you'd probably like this; if not, then not.
The stage show consisted of a set of demos with audience member participation, and a lot of talking. There was also some behind-the-scenes video played during downtime.
The demos tried to be in the spirit of the Mythbusters show, but simplified down enough they could be done in 3-5 minutes on stage. Here's Adam hanging from two interleaved phone books. Here's what happens if a big guy hits a thing with a small hammer versus a small girl hitting it with a big hammer. They were generally dull, though our kids seemed to enjoy them.
The stage show essentially rides on Adam's and Jamie's personalities. Adam's the expressive, emotive comedian and Jamie's the stoic serious guy. They took audience questions. They told stories. They explained some of the history and motivation behind what they do. If you like the show, this was excellent stuff. Honestly I could have done without 90% of the stage demos and just had a couple hours of anecdotes and Q&A with props. I give them credit for trying to do something different, though.