One also has to remember that international Hyatt properties act very differently from the US. AFAIK in Asia, the Hyatts there want you to pay at least the worldwide corporate rate before you will be considered for any sort of upgrade.
I've never liked the GH HK only because of its far away location from Central. But given the exhorbitant room rates at the hotel, I'll only stay there when I redeem an award. I much prefer the Hyatt Regency in Kowloon. I know some of you hate that property too but I get treated very well there, so I might be biased.