I'm relatively okay with booting up Windows 10 to play games, apart from the well-known upgrade practices, the inacceptable (if configurable) ad popups for Office 365, and my resulting lack of trust in Microsoft's future practices.
However, pragmatically, on all the Windows 10 machines I've typed on there seems to be a slight, yet easily noticeable delay between keyboard input and, e.g., characters being drawn on the screen, independently of the application. Whatever the reason (compositing? vertical synchronization?), I find this amount of input delay quite off-putting for everyday use and have not found any information on how to reduce it.
There are input latency measurements for Windows 7 [1]. I'm not aware of similar measurements for Windows 10.