BTW here is the data on the panel :
I have made a huge error. The Candian Solar panels will NOT charge a 48 volt system, since they are "on-grid" panels that have a working voltage near 48 volts. You need, " off grid panels like the one below that has a higher working voltage to get the electricity to " flow" to the batteries properly. There panels are apparently quite sturdy and will not need to be " marinized:
I've never had a problem with a solar panel installed on my boat. As long as the mounting is secure I don't see a problem. Just make sure no one can walk on it. IMO I think they are just protecting themselves from a bad installation on a boat not salt water. Otherwise they would not allow them to be mounted along on land on the coasts of Canada either.