Use ATM card to draw cash from ATM machine enjoys the best rate!!! That's what I did in Apr, I tried all methods (exchange in banks in HK, exchange in Berlix, change in Taiwan Airport, use credit card.......) and get the best way! But there is a charge HKD20.- to HKD25.- each time, and the maximum amount is TWD20,000.- each day per card, remind u use ATM card but not credit card with atm facilities (in case of retained card, atm card is more easy to replace!) Hope it helps!