I've seen dual wand-wielding wizards laying down the pain in playtesting. Each cast requires mana to cast the spell imprinted on the wand, so it's not like its a sure path to victory, but if the Mage has built up a solid base of mana, then it can be very worthwhile. (Just a sidenote, cheap spells seem to be better imprints on wands than high casting cost spells).