1/5 for ridiculous targeting. 4-5 times know I've been cheated out of a perfect because there was a single mob that got through because my turrets decided not to kill him, even though they were in range, and there were no other targets in range.
Amusing in concept, annoying to actually control. I had all immunized people in one state, no healthy people to infect, and still i get infected people magically appearing in the state. 1/5
Not even close to as good as the 2nd. Difficulty curve is way up as well, so if you haven't played the 2nd, you are generally not going to have a good time with this one. Many of the 'medium' levels seemed to be more difficult than the 'hard' levels. 1/5
It is easy, once you get the trick of it. Mulit attack, let them waste their soldiers on neutral sites, then take them over, make sure you time your attacks right.