Here's a couple rifles of mine M4 BlockII inspired AR: Colt Upper, Colt 14.5" SOCOM barrel, Surefire Socom 3p flash hider, Surefire M600 fury, Lanco Gripstop, Aimpoint CompM4 on an LT lower 1/3 mount, Matech rear sight, KAC Mk12 Taupe front sight, B5 sopmod gen2, ALG ACT.
My 2 Scars 16&17 both with PWS SRXs, Super Scar Triggers and Surefire Socom 3Ps. 16 has a Aimpoint CompM4 in a LT lower 1/3 mount and the 17 has a NF1-4 which was in an aero precision mount but has since been switched to a LT SPR mount.
My general purpose beater AR PSA Midlength upper with FN CHF barrel, PSA Milspec BCG, BCM Comp, Aimpoint CompM2 in a QRP mount, DD Omega 9 rail, BCM Mod 3 grip and BCM Stock.