Assuming that PRS stands for Precision Rifle "Shooting"? I really don't know.
From my experience, it all depends on what you're trying to get out of your rifle. I have made 1,000+ yard shots with a fixed 10x Leupold and (very recently) a 1,560 yard shot with a 6.5-20x50 Leupold. In both cases the target was steel, not paper, and no score was involved.
If you're shooting for score, whether that is 600-1,200 yards, you'll likely want more magnification. Many of those shooting that sport are shooting Nightforce in higher magnification ranges.