I played for a few hours last night, and while the concept is pretty good, I have to say it's not a good game. The game stalled out 3 times on the first 5 stages and I had to restart. It didn't freeze up, but I spent 30 minutes running around because the game wouldn't give me the next objective. After a restart it proceeded along just fine. Another time I was escorting tanks through the stage, but one got stuck behind a box and wouldn't back up or move. I had to restart again and the tank made it through just fine.
The 1 think that makes this game suck is the amount of damage the cpu can take. It takes a good 1 1/2 clips to take out regular enemies. The automated turrets take less hits to destroy than the enemies.
This game seems to be a cross between metroid, halo, and the star wars battlefront, or at least that's what I think they were going for. Like I said, they had some good ideas and concepts, but the execution of the final product is just sub-par.
Maybe the multiplayer is better than the solo missions, I hope so for their sake. This is definitely a rent before you buy.
If I had to give it a rating, I'd say 6/10 from what I saw of the solo missions.