I just purchased a Sig 556 form Gander and it has no sights(came like that NIB). I then went to Whittakers and discovered that the 556 is supposed to have BUIS on the rails but mine doesn't. The salesman told me I had an older model of Sig that came with rails only and no sights. Question: Did I get ripped by Gander(they matched cheapest price in town, BTW, I aint paying their full price) and possibly someone removed the sights or did Sig really make an older model with no BUIS? Another issue: When I was at Whittakers, they had Sig BUIS that I could purchase, but they were $151.00 and he said those were the ONLY sights in the world that would fit my rifle. No alternatives. I was trying to match up other, cheaper, BUIS that fit pic rails and he said they wont work. Is this also true? I have never owned a 556 and I find it hard to believe a rifle like that was made and sold with absolutely zero sights.