Very nice.
I have a 14.5" BCM upper with the standard FSB, and SOCOM barrel. I think it's also known as M4A1 profile barrel. Lower is a PSA stripped, that I put together, PSA premium BCG, and Primary Arms 5X prism with the ACSS reticle.
I keep it stoked with the Magtech 77gr OTM. Essentially a MK 262 load.
I like it a lot.