I guess I wasn' t thinking when I posted on this one. You are right. 5 gpp is 5gpp whether you are shooting 50, 60, 70, or 80 lbs. I guess the better question would be what is the kinetic energy difference? This is where the 80 pounds probably pays off, I assume. Anyway, I am in the market for a new bow. I keep going back and forth between the Patriot SC and the Liberty. I really like the brace height of the Liberty, but the ibo rating on the Pat looks really good, too. All other specs seem to be fairly equal. I guess I will have to go shoot both to really find out which one shoots better for me!!!