What they got right: In this story we watch Dash get used to life without his speed, something that has defined him almost as much as Mr. Incredibles strength and invulnerability. There are scenes with Dash and the other kids entering and leaving the school where everything but Dash is in black and white, focusing on how he's now left behind by the kids. This is a nice touch. There's also a bit of continuity, as we see Violet trying to reach her boyfriend using a long range radio, since he lives in the woods. (See the first mini-series.)
What they got wrong: Unless Mezmerella is somehow connected to Dash losing his powers (which would explain the power-swiping stuff), it seems a waste to use her as a set-up villain.
(Also points off to the solicitors for announcing a totally different story. Frankly, I'm not sure I wanted to read about a time-traveling younger Bob anyway, but this story is much more interesting.)
Recommendation: Dash is my favorite Incredible, so a story that focuses on him makes me very happy.