I'm getting ready to order a dozen of the Easton Axis arrows and I'm having a little trouble deciding between the 400's and the 340's. According to the arrow chart for my bow weight and arrow length I should shoot 400's. I am considering increasing my bow weight a few pounds which would put me with the 340's. My question is, if I get the 340's and don't increase my bow weight, what happens? Will the fact that these are a little stiffer make a big difference?