The best thing I can say about Windows 10 S is that it’s not Windows RT. RT ran on ARM processors, so you couldn’t run any of your existing applications on it. At least with Windows 10 S, you can run a few older Windows apps: Evernote, Slack, Photoshop Elements and Autodesk Sketch. But serious programs, such as Microsoft Office? Nope. Full Photoshop? Hardly! Full Autodesk? Don’t make me laugh! Heck, you can’t even run Office 365 on it — at least not yet, anyway.
This is not a small office/home office PC operating system.