I'm running Windows 8 Pro, Sonar X2, Motu 896 via USB, Korg USB drivers. No problems here, everything works great.
I'm getting used to not having the start menu. I'm just grouping shortcuts and folders on the desktop and taskbar. Plus I have a shortcut to the Programs folder pinned to the taskbar which is handy when looking for the seldom used apps that I don't keep shortcuts to.
I have turned off almost every tile on the start screen but the weather app is nice if I'm to lazy to look out the window.