CruiseDuds

We are heading to the ABCs at Christmas (on a cruise) and are trying to decide what to do on each island. I know Bonaire and Curacao have amazing diving and snorkeling. Assuming we'll dive in one location and snorkel in the other, then which one do you recommend for each activity? I'm getting the sense that there's no wrong answer, but I still want to hear opinions and recommendations (including operators for tanks, etc). ~ Thanks!