ORIGINAL: Highpower
Ah, the age old debate of which is better, the 444 or the 45-70. Always makes me smile. Being a 444 shooter mainly, I'll argue that the 444 will do anything the 45-70 will do, only it'll shoot flatter. Buy one, and you'll never look back!
But, the 45-70 can be loaded to higher energy levels, and it has a larger frontal area, which means, with the correct bullet, the 45-70 will kill larger and heavier game more effiecently than the .444 Marlin. I still wouldn't hesitate a bit to use either on a Grizzly.