Lady, I shoot the 3555 Gold Tip XT. I have a 26 inch draw, 4 inch vanes, a gross arrow weight with broadhead of 344 grains I tried the 75 and 85 grains and found that I got a better arrow flight,FOC and improved KE using the 100 grain when my Parker UL31 was set at 50lbs.The speed loss between the 85 grain and the 100grain was not enough to discourage me from making the change up in head weight. I now use the same grain weight with the draw at 57lbs for hunting and 60lbs for 3D.