Biggest issues are cost. Sat Phone requires that you know who you want to talk to, and you pay by the minute, or according to the plan you have.
On
SSB, once you have installed the
radio, which does cost a bunch and has its own challenges, the cost is free.
VHF is limited to
line of sight and so distances are limited.
SSB also has the option of sailmail email systems for very low cost--text only. OTOH, you must be listening to
SSB, so if you want someone to be able to call you in an emergency, sat phone is better.
Personally I believe more cruisers have
SSB than sat phone. But having both is really the best.
You pays your money and takes your choice.......