I think NE450No2 is an exceptional shot and an experienced shooter far above most of us here. So what works well for him may not have the same margin for many of us others.

However the 9.3x74R is not far behind a .375 H&H Mag so I don't see that it is that under-gunned.

Using it as a long range cartridge is pushing it a bit, but you can't argue the facts of its success in NE450No2's hands.