All fixes and release notes will be available in the official version. And yes, we suggest official version for production. The internal builds are useful when you are waiting for fix of a critical bug in the development process.
Additionally, if you still need the release notes to version 2011.1.419, I can find them out.
the Telerik team
If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to their blog feed