They're all fine. But, they changed the barrel profile post 2014 from a "lighter" (mind you, it is still quite a heavy contour) 1:12 twist 4R barrel made by Lothar Walther, and switched to a 1:10 twist 5R barrel with an even heavier contour made by Bartlein/Wintac. Mind you, this is for .308.
The newer barrels perform incredibly well and are more agreeable to modern ballistics and modern rounds. You can always get a new barrel, so I suggest getting what you want and what is within your budget, then getting a barrel you want down the road. Else, just buy with the barrel you want in the first place, and send it. Honestly, you can't go wrong and there's no rifle that is "flawed" that needs to be avoided... except the AW50. I won't go near that thing after reading how it was designed.