He He
Nice Question
I also had this Question some time ago
Well , I had been using Windows 8.1 Pro Lately and i then installed windows 10 Pro
My install was not correct .
So, My Windows Installer had Got Corrupt
So, I lost a few of my Files in order to Reset it
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Bottom Line : I found Windows 10 Pro Far Better than Windows 7, Windows 8.1 .
Reason : It has Direct X 12
And Updates Smoothen your System.
And One more thing : New Games and Softwares are Being Made Only Compatible to windows 10