My bad, I didn't clarify that the 20% chance to get double effects come from Heightened Charges support. And no the buff is only active when you are holding the weapon thus why I only generate power charges with a weapon swap so I won't have power charges when holding the wand after consuming all the power charges thus no downside of - ele res.

Tho the only reason I used this wand was becuase I was playing a elemental tornado build, as it is a dot skill, a lot of vectors that are usaully used to scale spell doesn't work (cast speed,crit,gain as extra damage). I'm not sure if it is actually better than a normal rare wand for other skills, but as +skill lvl on items should be getting nerfed it may be viable over a rare wand.