Speed or stability in flight (accuracy under adverse conditions)?????
The lighter broadhead is, of course, faster. The heavier broadhead helps up FOC (the forward weight of the arrow) and helps maintian stability in flight in conditions like wind or rain. I use 100 to 125 gr points on my arrows. A 2215 shaft with a 100 gr point and a 2213 with a 125 weigh close to the same, so I don't need to change sight adjustments. Both are accurate from my Excalibur.