I work with the NMFS out of Juneau. We use Iridium sat phones all over AK, from the Arctic to SE, and I have personally used Iridium when transiting the inside passage on my sailboat. How well they work depends a lot on where you are and what you are planning to use the phone for. Sat phones obviously work much better where you have a clear "view" or connection to the satellite(s). So, in SE and N BC we often find that we have no signal or poor signal quality because of interference from the mountains. This can severely limit voice calling ability. However, even when signal was weak, it was usually sufficient for sending email which takes less than a second to send. So, as a method for keeping in touch and to let people know of weather delays, etc. especially in the shoulder seasons (Fall, Spring) when weather can pick up quickly, I wouldn't leave port without one.
Hope this helps...
