I have been wearing out youtube listening to both sides of the argument on heavy vs light arrows and fixed vs mechanical broadheads. Here is my take and I would love discussion. This is also focused toward the whitetail deer hunter. Most modern bow setups will not have a penetration problem with proper shot placement. Deer are not overly hardy animals (in terms of the ability to be penetrated by an arrow) so outside of shooting one in the shoulder or spine, penetration generally won't be a problem. Fixed broadheads are going to give you a higher chance of killing if you do happen to hit bone. Anecdotally, it seems most people miss back if they miss, so you are more likely to hit guts than shoulder. However, in the case of The Hunting Public, a heavy arrow and fixed blade makes sense because they are intentionally aiming more forward toward the shoulder and will have a higher likelihood of hitting bone. Others who aim behind the shoulders, more toward the lungs, seem to miss back more often and a mechanical broadhead with a larger cutting diameter likely makes more sense. My conclusion? What types of ranges and shots are you prepared to take? That will determine which works best for you. If you plan on taking longer shots, better not sacrifice too much speed with that heavy arrow. Planning on aiming at the shoulder? Better have a heavy arrow and a fixed blade. And as someone else on here has as their signature, if you plan your setup for plan B, perhaps you are more likely to make plan B occur.