I've seen reports of NATO soldiers in A-stan complaining not to be able to return accurate fire at greater distances were they were taking rather accurate incommings from enemy Kalashnikov like weapons. Anyhow, being introduced in the Vietnam war, were it was pretty suitable for the then conditions of close in jungle fighting, the .223 caliber is now over 40 years old. AFAIK, engagement ranges have again improved since then making the caliber too small.
The 6.8mmSPC seems a nice solution here, offering superior performance while it can easily be adopted in current 5.56mm firearms with rather small modifications.
Anyway, a nice new concept I think.