I have a factory DPMS with 24" SS fluted barrel; also a Remington 700 and Savage 111; all in 308 Win. If there is a difference, the DPMS may shoot tighter groups; or maybe it is just easier to hold for shooting good groups. All of them can shoot better than I can, even from the bench.
All three have scopes in low ring mounts. The DPMS mounts are quick-detach. Or whatever that is properly called? I like that the A-2 stock fits my cheek just right for sighting. I have taken some flack for the low-mounted scope. I added a Limbsaver butt pad just on general principals; the pad needed a few minor mods (other posts) and adds a half-inch to length of pull which feels real good to me. CAA grip (Brownells) is good, too.
last, a rifle chambered for 308 Win can always shoot 7.62 NATO. A rifle chambered for 7.62 NATO can easily get dicey with the 308's. Check rules where you intend to shoot. Many ranges forbid FMJ.