Didn't read through the entire thread so im not sure what you purchased, but when i built my AR i went with nearly all Bravocompany parts. After all of the research i did last year i learned that Bravocompany was one of the few companies that was making parts to mil spec for a great price. Delton, rock river, ETC do not make the parts to MIL SPEC.
Oh and the hottest caliber out is the new .300BLK by AAC(Remington)
.30 caliber AR that uses standard mags and really throws some lead around

(Its basically a .300 whisper)
This is my BCM(Bravocompany) AR in 5.56 with an Aimpoint T1 and a few Magpul goodies.