In my experience of hunting Russian boar for the better part of 20 years now, there are few round that match, let alone exceed, the killing power of either the .444 Marlin, or the .45-70 Gov't.
Yet, people call the .375 H&H Mag over-kill?! Seriously? The boar I have killed with .444 and .45-70 have dropped within 15 feet. Some dropped instantly. The boar I shot with my Sig-Sauer 202 Safari .375 H&H Mag, with factory loaded Federal Premium, 300 grain Nosler Partitions, ran 200+ yards, and took near 3 minutes to drop-dead, and nearly 4 minutes to "expire". I hit it 2 times at 100 yards, and took out the heart and lungs.
Give me a big, slow bullet any day. Ain't no such thing as "over-kill", but in someone's mind.
Geno