satphone rental

I don't have an answer for you, but will be looking into this before the February Prep Seminar.  In the meantime, if you plan to use the satphone for data, make sure that your rental gives you everything you need -- the basic rental is probably for voice-only.  Take a look at Global Marine Networks (http://globalmarinenet.com/) -- they do rent satphones and provide data services.  I've not rented from them, but I use their XGate data package with my Iridium satphone and they do know their stuff.

I also highly recommend an external satphone antenna.  The rail-mount one is best, but I've also had good results with the "hockey-puck" antenna taped to the underside of a deck hatch.  If all you want is to make voice calls from the cockpit (or liferaft!), the regular antenna is fine.