Not sure, since I built my two from kits 10 years ago. Real gawd awful Fankinrifles, but they work flawlessly.
A lot of people seem to like the new S&W AR due to it's price point and high build quality.
Ruger has a new AR out with a piston design instead of the dreaded gas-tube. It looks like a good value and Ruger is a decent company in my book.
Sorry, see now you were interested in .308 ARs. Smith and Ruger ain't goin' there, yet. If that's what you want then it's gonna be an Armalite or a Remington. Who else makes a .308 AR? Seems like there was one more.