GMMAT

There's a few factors I'd consider, but the bottom line is....."I" believe mass weight (to a point) is your friend. If you had to achieve this with a large dia. shaft, though....I might change my tune.

Flatter trajectory, at known distances, is NO BENEFIT. Given the information above (and assuming I'm hunting whitetail deer and smaller game), I'm shooting the heavier arrow.

IMO, the best thing a bowhunter can do to ensure he gets maximum penetration......is shoot a razor sharp broadhead from a well-tuned setup. At the distances I hunt, an arrow with a lot of mass weight is my friend.

Good luck.