I am using the configuration management tools in 2020x. Currently we are using Predefined Configurations to open a 100% BOM based on Model Versions, and will soon start to use Variant effectivity. What are the benefits/drawbacks of using Predefined vs Product Configurations? If I set up rules for the variants, will predefined configurations look at the rules to see if the variants I selected are compatible or not? What are the fundamental differences between Predefined and Product Configurations?