Nx8 imo, the 4-16 atacr has the same small fov as the 4-15x50; the nx8 has glass as good imo, a better power range, a cooler view unless you like the warmer view of the atacr’s, also great btw, nx8 30mm tube is for ma an advantage as well, the single and only advantage to an atacr is the eyebox is more forgiving and glass is probably a bit more consistent from scope to scope. I’ve had nx8’s that have incredible glass and some that were less that expected. Never had a bad atacr.
My fav atacr is the one most guys bag on, the 5-25, sold my 4-16s and my 7-35’s. Actually the 7-35 were more like the nx8’s, picker eyebox, smaller apparent fov at same power, and cooler image.