Win 8.0 / 8.1 works for me. The way I like to use it – is to only use “Metro” style apps for non-music/audio related things. I ensure that none of the apps run in the background, and I can swap between the desktop and Metro without the fear of some background windows activity screwing up my audio. I just upgraded to 8.1 and after upgrading the Quad-Capture divers and my Video card drivers, every thing is A-OK.
All of my audio devices below work perfectly :
Focusrite Saffire Pro DSP
Roland Quad-Capture
POD HD300 - I use the USB interface on this for doing guitar & bass tracks to avoid having to think about latency
Computer :
ASUS Z87 Pro Motherboard
Intel Haswell 4770K OC to 4.5
Several 2 TB Hard Drives – Window boots so fast I don’t see the need for an SSD.
AMD R7 260x Graphics Card