Powerful is high in fat, so it is meant to add conditioning. The ultra full and depth charge are similar in that they are meant to a) add fill for a full look prior to showing b) add depth of body if fed over a longer period. The depth charge and ultra full target different areas of the body. The Champion Drive is meant to add muscling (hence the high protein content).
My advice to you is to think about; how much time you have left to get your animal ready extactly what are you trying to accomplish. Be careful with the Power Fuel and Champion Drive. Its easy to over do it with those two products. A little goes a long way. The content vs the amount is misleading visually. They are concentrated.
Contact Purina directly. If you e-mail Dr. Kevin Burgoon. He will respond to you. It may not be within a few minutes or hours. But he will respond. Good luck with your project!