Look on the brightside, you'll still level faster than most and with a great deal of ease in comparison.
I love my mage and the penalty really doesn't phase me much, what other classes can sit down oom and still suck back some exp while medding?
[You must be logged in to view images. Log in or Register.] That alone makes up for the penalty. I know at later levels that won't be as possible but you'll still chew up exp bars faster than most.