In your comparisions, note that you can get an annual subscription from predictwind, and you can cancel it early and they will give you a credit of the unused portion. You can then restart later. The same is true for upgrades, if you want to have the pro subscription for a
passage, you can pay the $249, and when the
passage is done, downgrade back to standard and the unused portion of the
money is credited to your standard subscription.
When you combine this with only activating the Iridium Go for the seasonal months you are sailing out of
cell phone range, the package of the Go and Predict wind is much more reasonable.