Responding to ROOTless' comment on 1st ed. mage's. Keep in mind, that 1st edition had the Target # vs. drain equals Force + Modifier and not F/2. A force 3 powerbolt and a Force 6 were hugely different leaps in the amount of drain between first edition and second.
God, it was AWFUL in first edition.
I mean T# of 9 to resist deadly drain from a Fireball? Gah!