I shoot a Mathews LX with Easton Carbon Evolution 400 spine and 100 grain Spitfires, I could not be happier with them, I have taken one deer with them this year, and it was a complete pass through, with a great blood trail, but on the other hand I shot a buck earlier this year, and got about 6" of penetration with Thunderheads, I am glad I made ths switch!