Geez, that's kind of like asking "Which do you prefer, eating or drinking?"
Handguns are convenient because they can be worn on the person without interfering with normal daily activities. Since the "best gun in a gunfight" is the one you can put your hands on at the moment you need it, it wins in this respect. However, they can't hold a candle to a rifle or shotgun for power and accuracy. Wear the handgun, keep a good rifle and shotgun close at hand and use the handgun to fight your way to them.