Mags. The system that accepts Pmags has won. This has been known for a few years now. Although it's frequently known as the SR25 or DPMS mag system it's actually the original AR10 mag. Armalite while not the same company as then did buy the name etc. So technically it is the Armalite mag. But for the current AR10 they went to modified M14 mags to avoid issues of the Assault weapon ban in the US. I'm in the minority as I'm not a Pmag fan. They're ok. But I prefera mag I know will work in all my rifles using that system. With the AR15 ones you might need different gens for the different rifle systems. I use D&H. Works in AR15, Tavor, Type97 etc without worry.