Personally I would stay away from GX12, just because there is so much utter junk out there in that format.
Lemo if you can afford it, quite excellent and really has the quality feel (Stay away from the fakes, mostly junk), or Hirose (Avoid the plastic ones).
Souriau UTS are nice as plastic connectors go, and (if you buy the right bits) are waterproof even when unmated which may or may not matter.
XLR has enough 'expected uses' that I would be a bit careful, but it depends on your market.