I would say Dragonball. But since it's not an option I guess Z. I haven't watched all of GT however, but it seems to have gone the way of the pokemon shows, less about story, character, and overall heart, and become more about pumping out as many episodes as they can so as to make more money. In its defense, GT does have a lot of heart despite what I just said, and it has its own unique sort of charm that still holds true to the characters. And in the end they are what really made Dragonball for me in the first place.