Yes BUT ONLY IF AFTER THE UPGRADE YOU SHOULD DO A CLEAN INSTALL
the upgrade breaks a lot of things if you don't do a clean install after it. 2nd for everyone complaining about privacy you can turn it off in the pc settings
You can remove cortana using a command line in power shell.
After reinstalling windows 10 i noticed like a 3 fps boost (nothing major)
The only real reason not to upgrade (and do a clean install) is if your system is incomparable with it(so cheek your hardware first.)
Juicythe title