Heat is not bad in HK (34C is pretty much tops), but the humidity is much higher than Dubai. Sort of like coming out of the shower the second you step outside. It doesn't cool down at night at all. And the air-condition in all public malls, hotels, restaurants, etc is turned up so high that you need a jacket. 10 years ago they measured 15C on HK buses in the summer time! It always feels like a cold winter day.
Besides, the days when you could find bargains on name brands in HK are pretty much over. Ever since the days when mainland shoppers descended on HK stores in greater numbers -- and they are used to very high prices for real name brand items at home, besides in HK they feel more certain that they won't get stuck with fake goods.