I recommend full reinstall. I always do that with every computer, every OS. It's probably a smart thing to put it on usb flash drive first. It installs in 20 mins on slowest computers that way. I've got MSDN subscription so I have tested all betas, rcs and pre release.
If you are sporting around SSD and you're worried of loosing data then you're doing it all wrong
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Full install is the only way to make sure it works as intended.