One major question is 'What exactly is going to come out the end of that thing...ammo wise', and are they fielding a GPMG in the same caliber?
I know the following will get me hosed on this site....but.....the venerable 5.56 is a 200 yd round in the 62 grain variant. From what I've read (SGN), much better terminal ballistics are available with the new 77(?) grain pill and pushes the envelope out considerably. Unfortunately the AR needs a new (longer) barrel and a fricking armorer to be 'upgraded'. Now before you hit the reply button, think about it. The 5.56 started life as 55 grain, then 62 and now 70-something. That tells me that its lacking something and the MIL guys are trying to fix it. Short barrel carbines don't help the situation either. Issuing an upgrade and new ammo is a hell of a lot cheaper than issuing a new rifle in a new caliber too.
Our boys in the sand box have been damned fortunate that an AP type round capable of defeating their body armor has not been widely used on the battlefield. That's one reason I cringe at the possibilities of hundreds of millions of Chicoms armed with a much better rifle than the AK in either 7.62 or 5.45 and capable of penetrating state of the art body armor.
What say you?