All I hunt is deer, I suppose I might think about increasing arrow weight if I was going after a moose or grizzly. Ive seem my set up blast through too many very big midwestern whitetails to be concerned about penetration. I just prefer a faster lighter arrow. In my opinion it gets to the deer alot faster, so less chance of them jumping the string, it shoots flatter aiding in misjudged distance, and Ive never had problems with penetration. Even on bucks that go 300+ pounds on the hoove.