An easy 200 Gamerscore.
The gameplay is simple. There are two campaigns to play in. The Dino campaign and the Truck campaign. In the Dino campaign, you play as a T-rex and you have to eat a bunch of Doritos before other dinosaurs can get to them. You also gain a bunch of powerups along the way. In the Truck campaign, you play as a truck and you need to pick up Doritos while avoiding dinosaurs. Both campaigns are pretty easy to complete.
So, should you "buy" this? Why not? First of all, the game is free. Plus it has easy achievements. You could probably get them all in under 20 minutes. No joke. This game also really doesn't have any replayability at all. Once you get all the achievements, you'll most likely never even play it anymore. If you want another 200 Gamerscore added to your GamerTag, then I would suggest "buying" this game.
I give Dash of Destruction a 7/10.