Thanks for all the help guys...
We certainly wouldn't marry just to make visa life easier. The gf is applying to study for a PHD at one of 3 Universities in HK but they won't confirm the place until April (despite application date being Dec) and we move in Jan. Was hoping she could work the 3 months in between but if not, then so be it. She'll be equally as happy doing some voluntary/charity work (if that's even allowed).
Looking forward to the move and I'll def check out the locations mentioned online.