If you are working with Git heavily like me you probably want a customized shell.
It lets you know exactly where you stand without typing anything.
It saves you time typing git branch to know what is the correct branch. It let's you know how many files are uncommitted/added, what revision are you looking at and much more.If it saves you time you should probably use it. Because if it does it allows you to focus on what's important - your product.
Hooks are scripts that help you enforce policies on your repository by triggering scripts at certain events that enforce policies such as 'The commit message must be longer than 20 characters' or 'The test suite must be run before a commit and if it fails, reject the commit'.
Hooks are available in every VCS I have used before. They are also available in Visual Sourcesafe which is not a VCS.