Im shooting goldtip 7595s, total arrow weight of 395grains, I may bump it up to 420 when Oct 1 comes, not sure yet. Mind you, I havent shot the 300 model but the guys at the range who have tried them perfer the 400, Im guessing because the extra support for the heavier arrows makes it less likely to get knocked out of tune while dragging it through the brush. Good luck, keep us updated.