Haven't been to Hong Kong since 2004.
And lived there from 2000-02.
So I can't really remember things.

1) Are the sport items there like shoes, apparel cheaper than in Malaysia?
  cheaper but not much. ard 20-30% avg. But more choices esp those special releases.
2) Does the factory outlets for Adidas and Nike sell good stuff or outdated and really non-desirable (leftover stock) stuff?
  Usually past season stock will be very much cheaper up to 50%. Its dated but not really leftover. eg 2012 sells 2011 jersey
3) Is the weather there now same as Malaysia or a bit cooler?
E.g. is a 30 degree C the same as a 30 degree C as in Malaysia or is it less humid there?
Almost same but less humidity though might experience sunburn easier
4) Is the expenditure for eating out much more expensive than in Singapore?

Thanks!

So I assume eating out is around the same price as in Singapore.
Hmmm I wonder why some of my friends said that HK is much more expensive.

One more thing, I want my little brother who is in HK now with my family to have a data/voice sim card. Which one would you suggest?
Why I want him to have data is so that he can whatsapp me.

I read somewhere that one of them is one2free by CSL.
But so many conflicting stories.

Thanks