There is no doubt that Predictwind is a good resource. The full package is US$500 which is about the same price as my annual satellite phone bill. There are many free weather resources which probably source their information from the same locations as Predictwind. I use Passage weather which is a freebie. Sailing Weather - Marine Weather Forecasts for Sailors and Adventurers - PassageWeather
Also take a look on Noonsite for other well researched weather links: Weather — Noonsite
Hope this is helpful.