Meng_Tze:West Palm Beach (FL), UK, Singapore, Thailand....... To me its a matter of 'the world needing to know and accept GUE as a cert. agency.
While I'm not disputing the fact that some operators may shun divers who solely carry GUE cards, this is why every diver should keep an up to date logbook, and check with an operator long before getting there to make sure they will honor a GUE cert.
To be honest, If I'm GUE Tech 3 or Cave 3 certed and an op won't let me dive, I just simply wipe them from my list of possibles.