Gentoo compiles all packages from source and aims for stability, whereas Arch Linux installs binary packages and aims for the bleeding-edge of free software development.
From 12 feet, you'll throw a full-spin rotation. Grab the knife by the handle, as you would a hammer, but keep your thumb along the top edge for stability and to prevent over-rotation.
CentOS is an enterprise distribution, suitable for those who prefer stability, reliability and long-term support over cutting-edge features and software.