Ya, I would like to go into battle with a Ma Deuce but, that is not a very practical weapon to carry. I think another thing that may or may not have talked about here but, the bigger the round the less ammo you carry.

I have always been a location, location, location kinda person. It matters more where you hit someone than what you hit them with. Next come good ammo. HP ammo is the key. You get a 5.56 hp ammo traveling around 3k fps and I don't think too many people will be dancing a jig after that.