I've always maintained that you don't need a water maker to cruise down island. The cost both to purchase and maintain a water maker is not insubstantial. It's only been this cruising year (2010-2011) that I have changed my mind and will now be getting one for our boat.
In the years since we've started cruising advances in the construction of water makers have driven prices down and reliability up. At the same time, output from alternative energy proudcers (solar and wind) have doubled in efficiency, meaning we can make more power than we can use and so the feeding of another power hungry mouth (water maker) is now possible.
Although there are many places in the Bahamas where fresh water is available at little or no cost, the luxury of being able to produce crystal clear, fresh water every day on demand is just too appealing to pass up. Even though we don't have one installed yet, I can already invision a time when I no longer have to be the water Nazi and closely watch how much water Amy uses to wash her hair. Mind you I'll still watch her wash her hair, but for totally non water related reasons.
As an aside, pictured above is our previous water maker, Frank on Fat Chance. He thinks we cruise with him because we like him, but really it's just to stay close to his 300 gallon water tanks and his 6 gallon an hour water maker. This is by far the cheapest option for a water maker if you can work it out....