12 pounds ain't nothing <img src="/images/graemlins/laugh.gif" alt="" />

You BOB should be a balance between fuction and ability to safely travel over moderately rough terrain. Some may be able to carry 80lbs or more of gear safely while other's may be limited to much less. Practice with you loadout, a pack that you thought fit and rode well in the store you may be willing to throw off a clift after 10 miles of hiking.

Your goal should be the lightest fuctional kit possible... save weight on gear you have more room for food and water. Remember the truism, you can buy cheap and light equipment, cheap and durable equipment, but you can't buy cheap durable equipment... it just doesn't exsist!