Rolex price in Taiwan is not cheap when compare to the price in HK.
For example, EXII white dial. Taiwan list price is 144200. I don't know max you can get how many % discount. Assume 15% off, then it is 122570 which is about HKD 28500.
However, EX II list price in HK is HKD 29100. And you can get 15% off which will then be HKD 24735.