Hello @hoeken,
Welcome to the Peplink Community Forum.
Peplink Partners have access to extensive guides (including an Antenna Selection guide with details covering the marine industry).
If you want the ease of switching SIMs, look at using solutions to support the SIM Injector. The SIM Injector can work with the HD1 Dome & HD2 Dome, the MBX HD2 & HD4 models, and others.
Here are some specific articles to get you started
Where in the world are you based? We are in Australia, though you may have a locally based Peplink Partner who is a Marine expert.
Happy to Help,
Marcus 