BigShark...how can you say the .270 is useless in heavy cover or brush? Even a .458 win mag is likely to be deflected enough by even a small twig that you'll miss the target unless the animal is very close to the twig that the bullet hits. I'd rather take my chances with an accurate rifle and scope combo to pick an opening in the brush,rather than relying on a big bullets ability to "bust" some brush.

A .270 with a 22" barrel makes a nice lightweight,handy rifle in the thick stuff. Besides...shooting into brush thick enough to deflect a bullet goes against the safety rule that says you should be sure of your target. If the brush is that thick it's going to obscure your vision and you shouldn't be shooting anyways!