I agree with Xerus01. The bloons being worth 1/3 when you redo a level is dumb, too. To pay for the upgrades it will take forever. I'd just get bored. The other Monkey games aren't this upgrade intensive and it doesn't take an eternity to enjoy a max upgrade.
This game is kind of stupid. The repair is way too punitive. You can't ever catch up if you don't pass a level. There are other games with this premise that manage that better. It has potential, but you can't miss any shots and you have to upgrade just the right way or you get screwed because repairing is way too costly.
 "Bloons Super Monkey 2"){kind=icon}
 "Redneck vs Zombies"){kind=icon}
 "Killer Escape"){kind=icon}