The advice I often hear is: "Take the most powerful rifle you can shoot accurately, instinctively, without being concerned about it's recoil". Not having a double rifle, my choice has become a 500 Jeffery. That being said it's taken two years and 400 full power loads through it to be able to shoot it accurately, instinctively without being concerned about the recoil lol ...

A well placed 375 bullet is always better than a poorly placed 400 or 500 bullet.

Have a great hunt!