Hello all. This forum has already been so helpful for me...It is a great information sharing portal. Got my 556006 very late in the manufacturing stage...mine was built in September of 2009. JT007XXX. Put on an aimpoint Comp M3 with a larue LT-129, a set of Troy folding combat sights, Sig's 4x4 picatinny rails, and a harris bipod with the adapter for the rail. Next up gonna go with the Magpull folding stock...(the sig one seems a little flimsy) and some Pmags...I absolutely love this gun and do not mind buying after market parts to make an awseom platform even better...Great site...Glad I found it!