Just sharing my experience. I bought a Dell Alienware 17 R5 Laptop from a private sale. Awesome machine BUT Dell built these with no support for Windows 7. In other words I am forced to use Windows 10. I like 7 Ultimate just because it does everything I need, does it right, and always stable. Had I known that I would have Windows 10 crammed down my throat I would have thought twice. Good news is so far Win 10 is fine...just takes some getting used to.
“I bought a Dell Alienware 17 R5 Laptop from a private sale. Awesome machine BUT Dell built these with no support for Windows 7.”
Did you know those were also sent out from Dell new with Linux installed as an optional OS? They are already geared to run Linux. :)