Configuring your Service Provider through configuration properties is pretty straight forward and most configurations could be accomplished this way. The two limitations that exists are: You can only configure what is exposed as properties, obviously, and you cannot provide specific implementations or instances of the different Spring Security SAML classes/interfaces. If you need to provide custom implementations of certain types or a more dynamic configuration you'll need to use the Java DSL approach for that configuration, but as expressed before, you can configure as much as you can through properties, while using the DSL configuration for any dynamic or custom implementations configuration. You can mix the two flavors.
The following table shows all the available properties (Parsed from Spring Configuration Metadata file).