Looking for some recommendations. My setup--42# Toelke Whip wants a very lightly spined arrow--I am using beman MFX 600s and GT Blems 1535s full length and it takes 200 grains up front to get them tuned. I would like to be using around 135-150 up front and get to something closer to 10gpp. I have some Heritage 75s that I have yet to try, I'm trying to find out if they are the newer .670 spine (they are marked 2013) or the older .611 spine before I break into the package and loose trade value if they are the .611s. I tried weighing them (the old are supposed to weigh 8.69 gpi and the new 8.80 gpi---mine w/o insert and weigh 9.8gpi so I will have to contact the mfg next week. I don't have a spine tester so don't know how to tell. Anyone have experience with the newer 75s that are .670 or the Predator 2 700s or if you have ideas of other carbons that hit around the 700 mark i'd be interested. The Predators look like a deal until you realize that inserts are not included... Thanks, John