Absolutely spectacular!
Love how using different colors of upgrades affect different towers, and how different the towers' characters are. The money concept is solved in a great way! As mentioned in others' comments, there is just right amount of animations, which is a great thing - the game runs smoothly.
Come on guys, where are mission packs/second part? Want it so badly!
5/5 of course!
The controls are a bit weird, but I really liked it after a while. I think the control system is very creative! 4* from me! (I think 4.5* would be more accurate).