TyroPicard is right. the main prosedure reccomends you to use the CG from the load sheet. but! Who knows that the figures from the load sheet is right? We have to believe in that figures and in your experience. I can remember the takeoffs when the real CG differes from the load sheet. You can feel it during rotation. The forward CG gives no sufficient problems, but with the aft CG just bee careful to avoid tailstrike!
Be happy, Pensador