I just got a new dozen beman ics hunter 340 shafts fletched last night. I am using 3, 4 inch duravanes fletched at 4 degrees. I am going to be shooting 67-68 pounds on a mathews lx, with 100 grain muzzy broadheads. My total arrow weight is 437 grains. using a 30 inch arrow. My question is if my arrow are a little to heavy for all out speed, since they weigh in at about 6.5 grains per pound of draw weight, or if this is a good compromise for speed and quiet shooting?