Hmmm interesting. You would sure think if this was the case, it would have been on demo like the new HK416A5. When I saw that one I found it interesting because I went to Adventure Outdoors store in Smyrna, GA last week.....asked the guy behind the gun counter to check on possible shipments on the MR556A1. He pulled it up in their system and said "you mean the MR556A5," and I said no. He turned the monitor around to show me and sure enough it said MR556A5. I just chalked it up as being a mistake, but now I am very curious.