Whether you buy a 3 or a 4-blade ceiling fan will depend on your needs. The option with fewer blades will likely move faster and move air more efficiently, meaning a higher airflow. This is because fewer fan blades lead to less drag in the motor of the machine.
On the other hand, ceiling fans with more blades are often quieter, which is essential to some of you. As such, you’ll have to pick from these two options depending on the benefits you prioritize.