I take Kittylock's advice earlier to buy in Commercial Press. Now 15% off. With every purchase over 300, another $50 off. So, overall is almost 20% off. It is the cheapest way in HK that I can get ORT. The only drawback is not many stages are available in CP.
Even though the price is a bit high as compared to other China published books, the quality is worth the money. So, eat less and dress less and save more for the books. In fact, I really enjoy reading the ORT. I think I am intrigued already.