My monk (Windwalker / Mistweaver) is equipped with some Deadly Amethyst and some Flawless Deadly Amethyst, all rank 2. Setting desired gems to Epic and Quality 2, it is recommending that I downgrade all of the Flawless Deadly Amethyst gems to Deadly Amethyst.
That’s a direct downgrade, losing 4 Mastery and 2 Critical Strike per gem downgrade.