Burning Legion is one of the ones that gets intermittent Hardware upgrades over 5 days, so it was pretty laggy for a while, and had quite a few guild members bitching about rollbacks.

Luckily (or unluckily), I hadn't experienced any. If I had, I was going to try to get multiple quest rewards, like I've heard about.

Some guy on our server got 2 Thrash Blades.