The loans are fed. if you go private your options for repayment plans are more limited. Depending on your situation you can live on less than the "budget" the school produces. We had it increased this year because many of us were not able to make ends meet. I have a wife and child, life insurance, health insurance, and numerous other expenses from my pre-med school life that many others don't so i have used every dime i could get.
you can always take out the max $$ and then pay what you don't use directly back to principle when you decide you don't need it.