I would go with the G3 for the 308 Win round. A 308 round is much more powerful, and the inherent accuracy of the G3 is much better than an AK47.
Very good rear sight, however the windage adjustment screw will only move the base when the lock screw is loosened (Phillips head screw). And then, the windage adjustment is not precise, very loosey goosey movement to the base. Which is why I painted that line, so I could find zero again if the lock screw got loose.
I paid a gunsmith to do a trigger job, and this trigger, after the first stage takeup, is as crisp as a match trigger.
I consider the retarded, or delayed blowback bolt a marvel of engineering.
This gun works by floating the upper 2/3 of the case from the chamber walls.
Gas lubrication breaks the friction between case and chamber, but it is function critical to keep the flutes clean, and not use ammunition that will clog the flutes
PTR had a long list of surplus ammunition that caused their rifles to choke. Tar sealant was one of those things that clogged chamber flutes. So make sure you buy a chamber brush, and keep that chamber clean!
PTR puts on match grade barrels, with ball ammunition, it will hold the black at 200 yards. It is more accurate and more powerful than the AK 47.
That 5V target, that was used in the M1903, M1 Garand days. All you had to do was hit the black, and you got the highest score possible. Somewhere before the 1960's the V was added to break scores. Holding the black was all an American service rifle was expected to do, and be combat issue.
At least in the US you can buy all sorts of G3 stocks, optical sight arrangements, etc. An individual can really trick the rifle out.