X 2. It doesn't matter what WE like. YOU are the one that has to look at it the rest of your life. Go through some deer hunting magazines and find a pose that strikes you. Take that picture to your taxidermist and ask him to duplicate it. Don't rely on other people's opinions about what YOU are going to have to live with.
The 6400's face is too thin..especially the bridge of the nose. Between the 2 you chose the 6900 is the best. Ohio Taxidermy Supply has, without a doubt, the best sculpted form out there...period. My opinion. Although they don't have too many sizes yet. I agree with the others that it is up to you, not us, as to which form you choose. Good Luck!