Depends on the arrow you choose and what you're trying to accomplish. To me, I like a heavy arrow and I like a heavy FOC. To get the proper balance and consistancy I want it's always going to be a 125 unless I go to a lighter arrow(which I won't). It'a a balance between shaft and broadhead. If you select an arrow that's too weak, you may have to go with the lighter head to maintain the spine. If you go with too stiff an arrow you'd probably have to go 125 to weaken the shaft a little. You don't select a head weight to just beable to shoot that head weight or have a heavy head. You select it to balance the arrow with your bow and get the best performance for what you're trying to accomplish.