Dual LMG build to maximize 12% LMG damage roll.
Great for underground as well.
Big Alejandro due to 50% damage increase during cover.
I like the MG5 due to RPM. I've tried other LMGS but they're boring to shoot. I guess you could do hungry hog as well.
Ammo cache just because you'll stationary a lot and saves your ammo. Tac link with lonestar ult pop would be insane RPM. Smart cover, just choose whatever. I like healing.
Double barrel for sidearm due to shotgun dam increase from Lonestar.