After a lot of research on the internet, I'm pretty sure that I'm going to purchase a Remington 870 XCS Marine Magnum 12 ga. Its intended use will be home defense, but also maybe as a secondary weapon for white tail. I live on an island off the coast of Maine where the air is very humid and salty. We have rust on things that you couldn't imagine, so this is why I like this particular gun. It comes with a single bead sight. Does anybody know about putting on a different type of sight to make it more hunting applicable, and if so, will this affect the nickel coating in any way? Any other sights commercially available or should I bring it to a gunsmith? Any help would be greatly appreciated.