Genuine Miele Bags are not only guaranteed to protect your vacuum but they also ensure that the 7 year motor warranty is protected! Genuine Miele bags are specifically designed to trap dust and ensure maximum airflow. This makes your miele vacuum run better with more suction and the motor runs cooler helping it to last longer. We never suggest risking non-genuine bags. The cost savings, if any, are always lost when the motor fails sooner than if genuine bags were used.