I love the game, just like 1 and 2!
However, I was suprised to find that the wasted balls are recycled. Takes the edge off the challange, really. But it doesn't make the game less awesome. 5/5!
Slighty easy actually, you barely need to get upgrade, and you don't need the explode/bullet time (it's helpful, but far from needed). Everything else was fun tho!
 "Factory Balls 3"){kind=icon}
 "The Next Floor"){kind=icon}
 "Death vs. Monstars"){kind=icon}
 "Powerpool 2"){kind=icon}