[sofaofthedamned]

At a previous contract I built a VM environment based on KVM. Some of the VMs were Windows, some Linux - a mix of Ubuntu and RHEL. It was a secure environment, where part of the job was malware analysis, so obviously part of this was nuking VMs and reinstalling them.

Anybody who has done this knows with Linux it's easy - RHEL/Centos and Kickstart files are the best, because they work. Next best is Ubuntu/Debian as Preseeds work but they're bloody awful. Once you've got one that works you're fine.

I had all the Windows 10 VMs with 'Professional' keys. Now, I imagine like you i'd suspect a 'Professional' key would imply this sort of lifecycle - rinse, reinstall. This worked for the first month.

But...

Part of the install was getting updates from WSUS, which itself is awful. Turns out halfway through our build Microsoft decided after these updates they'd change the rules. So, where I was providing the autounattend.xml (ks / preseed equivalent) this particular update decided my keys were not worthy. Professional wasn't good enough, when it was previously, so I now needed Enterprise. So none of my VM rebuilds would work without intervention. These are headless VMs. This cost us tens of thousands in engineering bucks.

If I started a company tomorrow i'd go nowhere near Microsoft. I'd not let one of my employees get near a place where they decided business logic needed to go into an Excel spreadsheet. They'd have a Chromebook and i'd pay the $6 a month for them to work without any of the extra crap Microsoft decide to do this month. Yes, Google can do the same, but i'll take the chances at $6 per month as opposed to the Windows, RDS and assorted other CALs that Microsoft decide to do tomorrow. I'd even go to O365 if I trusted them after this. Which I don't.