Another option is to find an operator that stays over in Mersing on Friday and depart for Tioman/Aur on Saturday morning. The travel time is still the same but its much more comfortable that way. I did that with Fishermen Scuba. We leave Mersing at about 7-8 in the morning and by 10-11, we were ready to dive Renggis in Tioman before we even set foot on Tioman island.