If you had to choose between an AR in .223 or .308, which would choose?
I made my choice, 5.56 (.223)! The good thing about my LMT MRP is that I can also have other flavors without purchasing another rifle. 
In my mind…2 different cartridges for 2 different uses.
.223 for CQB because of recoil control, “Proper” (not over) penetration and fragmentation, reliable platform, lighter ammo, and you can load more of it into the weapon.
.308 as a “Stand Off” weapon for ranges past 250 yds., hunting, “Tactical Sniping” etc.
I use to be a big .308 fan, and still am, but I can’t imagine my CQB piece being in .308. Too heavy, too much penetration, too loud, less rounds in the gun etc. My .308 is a 7 lb. Rem. Scout Rifle (one of the Original Configurations). 308’s in AR platforms are “Heavy Beasts” IMHO. YMMV
Tack
I like .308 better than .223 but not in the AR platform.
Exactly.
Unless you’re a Portuguese soldier in Mozambique…
