So basically, people recommend using Windows 8 instead of Windows 7 because you can make it just like Windows 7? That seems fairly redundant to me. Would you recommend it if you couldn't revert it back to looking like 7? I know I sure wouldn't.
Besides, one thing I would bet very good money on is that there will never, ever be a time when you will need to upgrade to Windows 8. DX11.2 is totally pointless, and not only is the next version not out yet, but the lag between its release and enough people upgrading to video cards that support it for developers to start making games that use it is going to be a good few years at least, let alone until games come along which won't work without it. Hell, most games still support DX9 and work just fine.
The amount of time before you will see any benefit to using the next DX version will be long enough that you can just skip straight to Windows 9, which will hopefully be better. Much better.