I've been playing with Windows To Go for 5 days now.
It's a lot of fun, but it has it's limitations.
In particular, it can't do Windows Update and I'm having problems with touchscreen drivers.
I think this is due, in most part, to the drive being a removable drive.
I've tried to convert the drive to a fixed drive and it works OK - but it breaks the boot stuff in WinToGo (so I can't boot and I can't repair it).
It's just to fussy for me at this time - I'm calling the experiment off and relying upon Win8 on my desktop.