Brutal Earthstorm Diamond

Simply click the white 'Chance to Stun Target' link found in the above item tooltip, and you will find out that the duration of the Stun effect is 1 second.

Here's a summary:

1. This is best for fast hitting melee classes, because of how +weapon damage works
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3. This will greatly improve skills that have high modifiers (e.g. Backstab, Ambush, Mangle).
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5. The proc is 1% chance to stun for 1 second, and its range is 5 yards (Melee)
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7. The proc will trigger the uncontrollable stuns diminishing returns timer (Unconfirmed)

Who benefits the most from this:

• Dagger rogues (All specs)
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• Feral druids (Cat)
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• Fury warriors (Dual wield + fast weapons)
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• Enchantment shamans

edit: As for fury warriors they benefit a lot from +AP, so a slow hitting fury warrior may not benefit much from this

I was super-pumped for this gem (being a dw enhancement shaman) when I saw it pre-bc, but 3 weapon damage equates to roughly 16 ap (2.6 speed mainhand/offhand) and the proc chance on the stun is 1%. Meaning 1 out of every 100 hits (mathematically) would proc this 1 second stun.

The boot enchant/meta combinations below would be tons better (assuming all other enh shamans value 108% runspeed as much as me):

Enigmatic Skyfire + Boar's Speed - 12 crit, 9 sta, 5% root/snare resist, runspeed
Powerful Earthstorm + Boar's Speed - 18 + 9 = 27 sta, 5% stun resist, runspeed
Swift Skyfire + Surefooted - 24 ap, 5% root/snare resist, 10 hit, runspeed

Keeping in mind that a.) all Boar's Speed enchants could be replaced with Cat's Swiftness (6 agi/runspeed) and b.) cost was not taken into consideration when writing this, as this was written to show other enhancement shamans what was out there, not neccessarily what they could afford.

As the game is now, I will be striving for the Powerful Earthstorm + BS combo for PvP myself as certain class(es) make stun resists and mass sta neccesary for survival in PvP, but when they get the balances they deserve I'll end up with Swift Skyfire + Surefooted.

Hope this helped!