I too considered getting this, but if you zero at 25 yards using the standard A2 smaller aperture (with Chuck Santose' Improved Battlesight Zero or equivalent), and confirm your zero at 100 yards, the larger 0-2 aperture shouldn't shift your zero to any significant degree.
If you use the rifle for competition, or otherwise honestly expect to shoot at and beyond 300 yards using the smaller aperture while reserving the larger aperture for 0-200 yards, then you can't do this, but many civilian AR owners DO simply use the smaller aperture for precision shooting irrespective of target distance (that is, including close targets), and if your rifle is zeroed this way, you won't likely notice any change in POI when you switch to the 0-2 aperture, just less precision. Best.
