Aldora provides exceptionally long dives by using high capacity tanks (50% more air) and computer aided multi level dives. Diving is done only the best dive sites to the far south, and in small groups of similar divers. They keep experts and novices separated and in different boats because they have 7 boats and work very hard to determine each diver's needs.
At Aldora they limit dive group size to a maximum of 6, and there can be a big difference in the dive quality between an operator who has groups of 8 and those with 6. Their average load is 4 divers and they always make sure that all divers in the group have similar skills and interests.