I am looking to buy a 20 gauge for my wife to use in emergencies. I would use it too but prefer my handgun. Is this gauge sufficient? My longest straight shot in my house is about 25-30' so what load would keep the spread down? Our room is on oppisite side of house from kids so if I fire it may penetrate walls. I have imaginary lines in my mind where I can't aim but I may not have the luxary of choosing in a real situation.