if you need windows 8.1 for anything but gaming or pro 3d then you can always install it in a virtual machine then you need not worry about supported drivers and timemachine will backup your windows too which it will not do with bootcamp
if you need windows 8.1 for anything but gaming or pro 3d then you can always install it in a virtual machine then you need not worry about supported drivers and timemachine will backup your windows too which it will not do with bootcamp