I'm rockin it Old School.
I love the 20" rifle and fixed M16A1 butt stock that has the shorter length of pull. Fits my short T-rex arms well.
But the jury's still out on that Barska 4X scope. I'm not sure that it's holding zero like it should. I need a couple more range sessions. It's a cheap replica of the old 1970's Colt fixed 3X or 4x scopes made for mounting directly to the fixed carry handles on the M-16s and the SP-1 rifles.