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Yes, all stanag should work.
I have noticed tho that mine sporadically has issues with M3 PMAGS 20 for some reason... (Doesn't lock on empty chamber reliably)
My ACR has functioned perfectly with every mag I've stuck in it. I've tried two different brand LAR mags, 5/30 and 5/20 Gi style metal mags, Hera Arms mags, gen 2 and 3 pmags, and my HK 5/30 metal mag. Some don't drop free but all function reliably.