I used Iridium Go on a South Atlantic crossing
last fall and and a Maui to PNW crossing last month.
Text messaging, email
worked well. For some reason my Samsung S5 was distorting when making phone calls this summer. No one else had that issue.
Primarily used to download gribs, navtex and weatherfax from saildocs this summer. I also had to call the owners a couple of times to deal with issues. Used Predictwind, text and phone last fall.
On SSB versus sat phone - If forced I would go with a stat phone. In 2012 during a medical
issue crossing from Maui the SSB was useless; we successfully used the sat phone to contact a Rescue
Coordination Center and effect a medevac.