The 400's at 26 inches and a 85grn tip would be perfect for spine, they would weigh around 355 grns, but the FOC is under 10%(9.7 according to the Program).

And I have not seen anything wrong with shooting short arrows, mine are 25 inches, but I would not suggest an overdraw to do it. The correct arrow length for a 27 inch draw would be 26.25. If you moved your rest back a little you get away with 25 inches. I don't think an inch or so would hurt things if you shoot well.

Paul