Difference between using dynamic_reconfigure and using getParam at runtime

I am trying to understand the benefits of the dynamic reconfigure package. From the [tutorials](http://www.ros.org/wiki/dynamic_reconfigure/Tutorials/SettingUpDynamicReconfigureForANode%28cpp%29), it seems like it creates a new server to handle a fixed number of changing parameters. What is the benefit of this (having a separate server) as opposed to using a getParam call in my code before using the parameter? For example if I have a parameter "publish_laser". In my node that publishes laser scans, I have a line that calls getParam("publish_laser") that retrieves the value from the parameter server, before deciding whether to publish the scan. Does using dynamic_reconfigure in this case make things run faster or show any performance benefits?