The 450/400 3 inch provides the best of two worlds. If chambered in a 10 pound rifle it won't beat you to death. It is small enough to find an excuse to hunt more often with it. It is big enough to swat whatever pops up outta the bush! In the 400 grain bullets are long and penetrate well!
Don't take my word for it, ask anyone who has shot an elephant with a 450/400 it does a great job.

The double rifle is a specific tool designed for a specific job. As we all know, that has never stopped us from trying to stretch the uses for our doubles. The 450/400 accomplishes this better than any other double rifle chambering! Loaded with 300 grain Hawks it makes a great North American round. Wharthogs to Elephants, you are covered!

Just my opine!