Concluding remark on this thread.
If the new, gee-whiz-bang rifle works as promised, nobody will be happier than I. My personal wish is for the USA's forces to have the best of everything. I am still leary of the 5.56 round's effectiveness at long range and though light masonry.
But if it does NOT work as promised, then there will be no new rifle forthcoming. As a precaution, it would be prudent to examine the best of existing sporting rifles firing more potent cartridges (such as the 6.5 mm Grendel) for a possble platform which could be modified for military purposes. Otherwise it will be the M-16 (and AK-47) for the next few decades.
I am always skeptical about new technologies until they have been proven.