I love my Black Rains. BR makes great guns and they're a fantastic company to deal with as well, should you ever have any problems. Anytime I do a billet AR build, its usually with a BR billet lower and a MEGA upper.
That's nasty looking, but pretty awesome too. I put a few hundred rounds down my Colt LE-6920 this weekend and need to clean it. You've got to love a gun that just keeps going. OH- Just got the new NRA catalog. Be busy for a bit.