Excuse me if this is hijacking the thread.

I have looked at the ballistics of the .300 Win Mag, .300 WSM, .300 Rem SAUM and the .300 RUM. Other than the power level III loads, I can't see a noticable difference in ballistics. I do see a big difference with the power level III loads but I wonder how much more those punish the shooter. Nothing comes for free. So, anyone that shoots those loads, can you tell me how they feel?