clemente21 wrote:
If your system can handle the newer O/S, you can clone your c:\ drive and upgrade there. If you don't like it, you can always put the old drive back.
And I believe you can revert back to 10 with the “go back” option, but it must be done within 10 days. After that, the option is greyed out and you must do a clean install of Win 10 (unless as mentioned above, you’ve cloned the disk)