I hear pretty much a kinetic energy vs. velocity argument. That one is better than the other.
I am shooting a PSE Drive LT with a 30.4" draw length and 70 pound draw weight. I am thinking that 420 grains (70 pounds x 6 grains) is the sweet spot for a balanced kinetic energy without sacrificing too much velocity. So I was thinking of getting the following arrow setup:
Carbon Express Maxima® RED™ 350 grains (cut to 29" which puts it more at 263 grains)
Carbon Express #1 Inserts 11 grains
Grim Reaper X-Bow Mechanical Broad head 125 Grain
That puts me 399 grains of weight. The Blazer vanes put it up to more like 410 grains of weight total. And the nocks like 420 to 425.