It is also a question of the weekly Windows security updates.
Windows 10 is safer as windows 7 or 8.1. If someone works with clients and needs a internet-connection, then safety is important.
We run 4 computer with Windows 10 without any problems and over 1 year. In fact 24/7.
We never would go back to 8.1 or 7.
All computer run SONAR very stable without any issues. The performance of Windows 10 is better then with 8.1 or 7. In Windows 10 the cores are better balanced.