This is not very accurate. the 5.56MM is a very nasty round.. it really puts the enemy in a lot of pain if they are not killed.. it is also easier to transport. But hey the russians were really stupid in adopting the even weaker 5.45MM round.
Man, how the hell will they recreate the XM8 in the next CS.... it will be like.. and smg, assault, persision assault, and machine gun all in one.. though i doubt they will include all four variants.