>>>have been contemplating getting one (and signing up with Microsoft to get the version of Windows that runs on it to play around with
>
>My understanding is that you need a PC with Windows 10 as the Raspberry Pi needs to be controlled by it- not just at setup, but at runtime. IOW not a distinct Windows device.

Hrm.. that sounds like a headless server configuration, though it does raise the question of what advantage you'd even get by running Windows on the Raspberry Pi, when you could probably end up doing the same with a copy of Linux.