I use Windows 10, and it works perfectly fine with WA 3.6.31.0 and 3.7.2.1.
Forced Windows update sucks for a lot of people, but I haven't had a problem with it, yet.
If you care about multiple desktops, then Windows 10 is for you.
They say Windows 10 is more secured from viruses, malware, but not from government agency.
I believe there was an update for both Windows 7 and 8.1 that enabled ease of access for third parties.
Although, you should be fine if you don't anything worse than pirating on both systems (If that is the intent of choosing an OS).
We're all in the system, whether we like it or not.
You don't have to use a Microsoft account with Windows 10.
In my experience, Windows 10 is fine, and so is 7.