For one day (which I happened to be raiding!) the Legendary Gem was stealth-hotfix-nerfed to 1/3rd it's damage. Supposedly. I was considering tossing it away for a normal meta. But I didn't. And the hotfix got rolled back.
The next item on the Wrathion buffet is a cloak. It's not just any cloak. It's a Bad-ass Cloak. The cloak is roughly seventy to eighty item levels better than what you have or may get. So it's worth doing the questline. (Cough.) I'm currently collecting more raid drops but at a frustrating pace. (I have only two stones.)