it depends which cureency u need, if u need TWD (taiwan money) KRW (korea money), THB (thailand money), MYR (Malaysia money), then SURE change at their own country.....
other currency just go to your own banker....
trust me, the currency i mentioned above i experienced b4, the difference can be up to 5-8%, even i am bank staff i don't used staff rate to change it in HK!
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