For sure you have to have both. Make a perfect shot on a megatron animal, say a large bull elk, a moose or some of the animals that are non dangerous but 500-600 lbs bigger with a cup & core bullet or a brittle cast bullet & bullet placement will break your heart.
It takes both & exits are always welcome when we pull the gun down out of recoil.
To put the emphasis on one without the other is asking for trouble. Take on something really big & dangerous & you just about guaranteed failure.
Vance with the bullets you mention I don't think there's anything up there that can contain one of them unless you are shooting them lengthways, those are mighty fine bullets.
If you need need some heavy weights PM me an address & I'll send you some. They will be powder coated either red or black, your call.

Dick