Randy,
I like metal roofs; however, I know nothing about their durability in a salty environment. I have no metal roofs, because I did not have the $$$ when any of my roofs were installed. I have helped install the pre-fab metal roof panels on friends' roofs.
I had a friend in college who dropped out to install and repair standing seal/seam roofs in VA. Some were well over 100 years old. This was far from the ocean in the Piedmont region.
My college uses terne-coated stainless roofs (and siding). Some is over 50 years old - no maintenance - installed by union-trained crafts-people.
This seems to be an informative and "even-handed" primer.
