Also the wand works more quickly than casting a spell, and you don't have to memorize that spell while you have a wand - so you can save your spell slots for something else.
The exception to this is magic missile - even if you have a wand, still have your mage memorize this spell, as the wand only shoots 1 missile, whereas the mage spell shoots several depending on the level of caster. BUT the magic missile wand can be used by any class with sufficient intelligence, so give it to one of your fighters who cannot use ranged weapons - this gives him/her a useful ranged attack.
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Time is an illusion. Lunchtime doubly so.
Epona of The Laughing Hyenas.