Yep, basting is necessary, you want to keep the breast moist and keep the skin from burning.
On another note, try this brining recipe...
Buttermilk-Brined Turkey | Williams-Sonoma
IMHO spend the extra money and get a farm fresh turkey, it may cost up to 3x more but the flavour is well worth it. Check out your local butcher shop and see what they offer, I usually order mine from Jackson's Meat & Deli. Butterball is a no no...