Ok, registered_fugitiv:
It does not have/is not supposed- to be pretty...
it is what the M-16/M-4 should have been, a man eater. Motally wounding a badguy with a 5.56mm NATO round is great for wrecking the enemies infrastructure, and demoralizing his society. But it's bad news for your Rangers when the same badguy doesn't realize he's been mortally wounded, levels his AK at you and punches several fist-sized holes through some part of you that you are very much attached to.
The Badguy doesn't much care about wrecking your supply chain and burdening your buddies with caring for you.... he wants you dead, all stop, message ends.
The Rangers and brethren need a weapon that does this, stops the enemy like a freight train. Whats more, when it's empty you reach down, grab a couple handfuls of enemy brass, or better yet, a couple loaded magazines, and commence to cutting more of the MF's down.
I will say this about the weapon's appearence, and I bet you can agree with me on this... it looks dead scary. It would have to be brutally intimidating to watch US SOCOM operators gunning down your buddies with these monsters and and then see one finally point it at you... for one brief moment.
Then... lights out.