I currently am shooting maxima blue streaks and i really like them at this point but im trying to look for something a little lighter, i know that the blue streaks for the 350 spine are about 8.6 gpi if my memory serves me right, i was looking at either the mach 5's by carbon express or the easton flatlines, their both only about .5 gpi lighter but i also plan on cutting them shorter than my current arrows, i shoot 67 pounds at a 29" draw and i know what spine i would need for both arrows (I work in an archery shop and i know all of the specs of both arrows) im just wondering about the durability issue with both arrows, any first or second hand experince with either arrow would be much appericated Thanks!