Hi all, Me and my family have been discussing purchasing a shotgun. We don't hunt, so we're looking for a general shotgun that we can fire as a hobby and keep as a home defense weapon. I know more about handguns and rifles than I do shotguns, so I'd like to hear your opinions. I was looking at the Mossberg 500 and Remington 870, both look interesting. Ideally, price range should be $150-$300. Preferably, I'd like some room for modifications, such as adding a flashlight (and pistol grip, if that's recommendable). I'm not really certain at the difference between 12 and 20 gauge, though I understand 12 is more common, but 20 is tamer to fire.