The 458 Win with a good handload or a factory load at 2000 FPS or better is all in the world one needs on Buffalo..I would chronograph any factory round before using it however..

The 458 Lott is a hands down better round for buffalo, a real thumper..I have used/observed both in action on Buffalo..The Lott would be my choice of the two...

That said I prefer a 416 to either of them....and if I want a big gun, I will pull out my Searcy 470 double. Just my choice, not a condemnation of the 458s at all.....