I have Ultimate but, I can't see or anywhere that says this can't work using lesser flavours OR w/ Vista; dbl check, please & let me, us know, if you would be so kind, thanks..  I do know it will not work w/ XP, as the 'host'.  Course, lots of things don't work on, aren't designed for, XP, anymore.
But, maybe the understanding you & Joe have is correct.  Honestly, I never had any thought or reason to explore that aspect.  Be cool if you guys can confirm 1 way or the other.
And yes, certainly, this method can be use for dual-booting to whatever other than just Windows 8...
2 Windows 7s
7 and Vista 
7 & XP
Drew