Although they are fairly durable, longevity can hamper usefulness. It's easy to fill up by squeezing the clear side all the way, but it's not always easy to make it squirt on impact. You have to hit the target with the ball where you press to fill it. It's not always easy for every kid, let alone when you're in a crazy water fight! When you're older, it seems easier to break up. My older kids (9-13 years old) love them.