It's impossible to fully predict the situations we would find ourselves in and the emotions that would govern some of our actions. Who knows, I may turn out to be of the fools or one of the survivors. I like the idea of having the more powerful .308 in my rifle, but the weight could turn out to hinder my effectiveness. Also, the caliber and bullet type (FMJ, JHP, frangible) would play a big part.
Another weight comment:If there was only a 25 grain weight difference say 140-165 gr. bullet weight in your ammo choice, that 25 weight gain would mean a difference of 1-lb per 280 rounds (