I am planning a circumnavigation of Australia by sailing boat. I'm currently with Telstra as there coverage was superior at the time I signed up. What is Optus coverage like today, will there be many dead spots arround the coast.
That's a super exciting trip you have planned @Harro56,
I'd definitely take up the advice @Withy has offered up.
You can purchase a SatSleeve+ through Optus. It's a costly option, but perfect for this sort of thing.
For more info click here