I really liked this.
I got about 20 or so levels in. While the first few levels felt like they were strategy based, after a while it was trial and error for the most part. I'd just launch 4 balls in different directions and see where they bounced. Some levels were really tricky, and others were incredibly easy.
I did have fun though. I liked the "epic fail" moments where you killed the alien and then killed the dude afterwards. Nice little easter egg.