Looking to pick up an "all-purpose" of sorts. Home defense is the primary use, but also shooting clays would be fun. Not looking to 3 gun or compete or anything, just for fun. Also would be used as a deer gun (low 1/2 of michigan is shotgun-only.) I've mainly been looking at the 870 since that is a pretty popular choice, but there are a lot of different models. I'd like one with a mag extension, are they ever sold that way from the factory? There's a Gander Mountain close to me and I just wanted some general info before I head out there. Here are all the 870's they carry: http://www.gandermountain.com/modperl/product/catalog.cgi?cname=Pump-Action&r=browse&aID=510D2 Anyway, just tell me anything I might need to know. Thanks in advance.