Some of the core offerings in Solaris (ZFS, Zones, dTrace, mdb) were ahead of their time, arguably. And the implementation is far more balanced than what you se

Some of the core offerings in Solaris (ZFS, Zones, dTrace, mdb) were ahead of their time, arguably. And the implementation is far more balanced than what you see in e.g., Linux, with good central documentation. So if you have a system which was built on Solaris, it might be smart to keep it operating on Solaris because you happen to know the tools and so on. It's likely any greenfield tech is better built on other systems. I'd use Illumos over Solaris, or FreeBSD.