I don't find shock to be overly effective on Buffalo. Unless the spine or brain is hit or damaged the only thing that will drop a buffalo in his tracks, in my experience is when one or both shoulders is broken badly. With all else equal, the bigger the dia of the bullet if a solid, or the best expansion of a soft bullet inflicts a larger wound channel , hence faster bleed out. Personally I believe today's fine soft bullets are the real choice for buffalo if one is to be used exclusively, over the other. I personally use a combination of both, or NOW am looking hard at the North Fork CUP POINT, as a do-all, in a 470NE. It seems to expand just enough to make a bigger hole, but retains all it's weight to break bones, and punch through, for a good blood trail!

Between the .416 or 500NE to choose between, if both were in a double rifle I would choose the 500NE, if the .416 was in a bolt rifle, I'd then choose the 500NE again!