Thanks to all who chimed in, and particular Furioso, for the help with my thousand questions (okay it was only 5 actual questions and 40hrs over-researching on the internet). Today, I placed my order for a BCM lower, BCM mid-length upper with DD Omega 9 rail, and 2 30rd PMags. I am short a rear sight, but by the time all this gear comes in I will have saved enough to get a good flip-up BUIS. I was over thinking and freaking out over the minute differences and it finally occurred that they were all the same upper receiver, and the difference in cost was just the rail (except for the SS or BFH barrels). I almost got the Troy rail, because the sling mount was on the rail, not the front sight, but the info I found on Troy didn't seem like it was free floated, and I know the Omega is. My buddy ordered a Millet DMS-1 this week, and if it shoots good on his Bushmasater, I'll add one to my BCM later. I'm excited about this rifle, because I know its built to take abuse, which means it oughta outlast me. I also have a DPMS AP4 .308, and although I'm sure it will outlast me as well, the more I've read, the more I've learned that its more of a sporting rifle with "tactical leanings". I will give my AP4 this much though - it will shoot 1.25" groups at 100yds using iron sights. Can't ask for much more than that as long as it's reliable. Thanks again, and I can't wait to assemble it and take it to the range to shut my cousin and his obnoxious spray and pray AK47 right the hell up.