I like the .458 lott, one reason being availabilty of relatively inexpensive ammo and components. I also like the ability to shoot .458 winchester magnum, a caliber thats very common where big dangeous game are hunted. It's a major thumper in my book! I must admit I am not familiar with the .450 Rigby though. How is the .450 Rigby different from the 450 Nitro Express 3 1/4"?