I am not trying to convince anyone to change - as the difference on game between any of the 416 is not enough to notice - although I'm sure there are plenty who would love to argue that. I am not considering ammo available either.
But the fact is that the original 416 Rigby was designed for temperature sensitive cordite powder and as such requires an overly large action, and the orginal Rigbys were overly large rifles.
With any of today's powders it is easy to reach original Rigby ballistics with smaller cases and still keep pressures to acceptable levels for use in the tropics, while carrying a slimmer, lighter rifle.
For that reason I claim the Ruger is theoretically the best . The Remington is also good but, while the ability to use a shorter action may seem like nit-picking on the rifle range, when you are under stress it really is noticable. Bell and numerous other notible African PH's have stated so as well.