Found an English speaking discount taxi service, rates as follows:
Fare: $80 upwards get 20% off,
Sai Kung/Clear Water Bay to Airport: $260 (All inclusive)
Try to call at least 1/2 hr ahead to Ricky 9807-7839 so that he can find a cab for you. His group has over 100 cabs and its not just for Sai Kung/Clear Water Bay, Anyone can call and see if he has any cabs nearby.