It needs a bit of balancing, in my opinion. The heavy is not survivable. In the upper levels, agility is required to avoid the showers of bullets and the heavy tank doesn't have it.
A lot to say about this game.
The good: The gameplay is fun.
The bad: No save feature. The story sucks horribly. Please, next time leave story writing to the professionals. Your voice acting is horribly melodramatic, and makes me want to punch babies. 3/5
This is possibly one of the most amazingly ingenius games I've played all year. I loved the idea, and I loved the controls. Usually I hate games that have no story, but this was just very impressive.