A. Both cost the same amount of LDON points, and do EXACTLY the same thing. Why buy 2?
B. If you ever try this spell out on a melee who has a weapon proc (or in my case like 8), it will immediately be changed.
C. This spell fades before 1 min due to some buff slot issue or mass proc issue (Runs out of charges?)
D. You can reach 10k dps in a small time frame with this spell on a good melee class.. So in my opinion this is overpowered although you have to re-cast it almost constantly in order to keep it up due to it's poof rate.
The End.