I picked up the Target exclusive edition with the bonus disk. Total run time was approximately 8 minutes and not worth the extra money at all. The packaging is cool though and I like that I can change out the cover art.
I watched the standard bonus features and while it did give some insights into how the story came into being and some of the character development, I really felt like they were only skimming the surface. Specifically when they were discussing how they brought Tarkin and Leia 'to life' in the film. I think that they could have done a full disk just on this process alone.
I don't know if I've just become jaded by the depth of the Hobbit and LOTR bonus content and the ridiculous amount of detail they go into, or if it's really that there wasn't enough bonus content for RO. But I really do feel that they could have gone into much more detail, especially as this was the first standalone film from LFL.