I got three stars on Level 42 by using one shot to get the bouncy bullets and killing the zombie at the left, and finished the level with 5 bouncy bullets (so I used other five, I guess). Remember there are Few Shots bonus at the end of the level, so how many shoots you make affects your score (I got 9400).
You know you've been playing just for the badges when the game awards you the medium one on level 39, and you don't play the last level to complete the game.
When I saw 'Perfect Balance 3', I inmediately thought it was the same game... again. The formula IS the same, but the new art style and music make it feel like a whole new game. Most people just wanted new levels, but you did more than that. Great job on adding square and triangle shaped gems, and making level packs unlockable by getting gems - I'm not a big fan of scores.
Great job, again.
There aren't enough new things to call it a sequel. All we have is circular blocks, and a level editor. You should have released this as a level pack, and leave circular blocks and more new features for a version that suits better with the number II. The game is addicting as ever, and I will probably spend a while playing custom levels... but not worth a sequel with so few new features. 3/5