Edgedancer and Emperor's Soul were really excellent. The White Sand excerpt was okay, I don't think the format is necessarily for me. Hope of Elantris was a quickie, but having not read Elantris yet I didn't get much out of it.

All of the Ars Arcanum notes were great / revelatory. Shadows for Silence and Sixth of the Dusk were also both solid.

I was mixed on the Mistborn stories. Eleventh Metal was okay, Allomancer Jack was skippable. Secret History was fun for the cosmere implications, but a little meh as a story on its own.