The Rules Engine V4 is the most valuable feature. It's the system to write all of the rules that control the behavior of the website. You control the CDN caching configuration, but also rewrites, redirects, and all kinds of request transformations from the client to the origin server, as well as response transformation when the answer is sent from the origin server to the client.

The system allows you to deploy your ruleset in a "Staging" environment, so that you can test the behavior of the rules, using your real web resources. Essentially, you test your own website but without impacting production. Once your tests are done and OK, you can deploy the same ruleset in production.