DirSync enabled vs. Without DirSync

DirSync enabled vs. Without DirSync

We're in the process of moving some users up to Office 365, currently only for Lync Online.

Right now things are still in testing. During this process we are running DirSync to sync users between our local AD and Azure AD. I'm looking at updating our ADManager Plus User Creation Templates to ensure this happens as smoothly as possible, but I'm confused on exactly what the differences are between "Create in Office 365 (DirSync Enabled)" and "Created in Office 365 (Without DirSync)."

Can someone provide more information on what each option does/doesn't do?

Thanks!
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