The safety feature can be the most important criterion on choosing right trampoline for kids. The better quality costs parents more without doubt. To achieve safer environment, most trampolines come with safety net package including net and poles in order to prevent kids jumping off and land improperly. However after years of usage, parts of trampoline begin to wear out, which causes the potential dangers for users.
The other family (B) has a trampoline without safety nets on the side. They also let their kids (ranging from 13 to 5) and the neighbor kids play on it while the parents are not home.