The exchange places at the airport are expensive; best to use an ATM there.
There are reasonable and fair cubbyhole exchange places throughout Hong Kong, but on basic principle I would not use any in TST. Not to say you'll get ripped off there (and not elsewhere), but the likelohood is greater. Look for "No Commission" and check the posted rate carefully:there can be a big difference.
Yes, in Macau you can use HKD at par with pataca, though make sure you get HKD in return. If you're spending a great deal, there's a small advantage in changing to pataca first. Of course, the reverse does not hold true in Hong Kong.
Thanks.
Do you have any exchange places that you can recommend?
I heard the places inside Chungking Mansions etc should be no go areas for currency, is that right?