Which Non-Lethal Weapon has the best chance of success against pirates?

The survey so far is correct. Early detection is the key to fighting piracy. You have a lot of options listed in your survey but most are either impractical or simply not available. For example, the Optical Laser Distractor is not available for export outside the United States. The LRAD is expensive and easily defeated. Global rescue (a wonderful company) is not involved in fighting piracy. Slippery foam will hinder the crew or security team as much as the pirate. Sponge ammunition has to be very accurate and airburst ammunition is difficult to accurately deploy in windy situations let alone moving at 20 knots trying to be effective on a smaller moving target. I don't think I need to go over every item listed I think we get the idea. Early detection is the best option listed, but it goes much further than that. Proper response to the early detection is equally important.