On my collection of computers I have Sonar 8.5, X1LE, X3e, Home Studio and Platinum's last version. All run just fine on Windows 7 , 8.1 and 10.
There is some who believe W 10 updates will someday make Sonar stop working.
Personally I think that's being a bit overly paranoid, but I can see their point. Nobody really knows what the future brings right now. I'm optimistic that my future includes working with Sonar. If W10 kills that set up, I still have Sonar on W7 and W 8.1 which will not have the update issue.