Insurance, whether for the seller or the buyer, is about probabilities. Despite the expected weasel-wording of a liveaboard operator's policies, if a particular liveaboard operator is known to do what it can to compensate guests for trips the operator chooses to cancel for weather or mechanical problems, I would like to know that so that I can take it into account in weighing the odds. Aggressor, for example, issues vouchers. My random check of prices indicated a policy of the type people have discussed in other threads would be in the ballpark of $200-$300. Paying that much for each of a number of trips over the years adds up. This isn't like health insurance in the US, where a bad stroke of luck while uninsured could bankrupt a person; at the worst, a diver loses a few thousand dollars of discretionary spending money. In deciding how to place my bet, I would like to gather all the information I can, including both written policies and travelers' actual experiences with liveaboards and insurance companies.