All compliance work was done by Mike at Allstar Tactical. He pinned the stock to prevent it from collapsing, and installed the block to prevent the stock from folding. Both of which, are not visible at all on the rifle. He also pinned the muzzle brake in place for me. I feel he did an excellent job, and if I get a SCAR 16S, I'll be going through him again!
The unicorn magazines:
Note the back of the mag where it extends out. There's a slot in the mag well for this as well. No idea what purpose it serves.