I'm confused actually....Did he say 350 GRAIN arrows or 350 SPINE?? In your DL and weight you should shoot a 340 spine, or 350, pert near the same....

If he is referring to 350 grains, that's 5 grains per pound, the lowest ANY manufacturer recommends. Personally, I've found the "sweet spot" to be around 5.8 gpp.....But that's just me.