Windows 7 Which Windows Do You Use?

I use a lot of them, but mostly as VMs I use to try and troubleshoot issues. Windows XP, 7, 8, 8.1,10 and Ubuntu VMs as well.
It's been almost 20 year since I've messed with Linux. So at this point simple and easy would be best I think.
Also using Windows 8. I find that Windows 8.1 improvements were mostly for the Metro side of things. Very little change to the desktop. Besides I update with Server 2012 updates, so I can patch the OS past it's January 2016 support cut off. That means no telemetry updates or CPU blocking. Win Win.

Faster and more responsive than Windows 7, and if you use Classic Shell, the metro start screen and charms are hidden.
I often use my lounge window waiting for updates to download and install, through my incredibly slow internet connection.