Whoah, what a coincidence! That's my favourite one too!
But seriously though, 9-Volt is one of my absolute favourite WarioWare characters, because I used to be just as much as a retrogaming nerd as him, and to an extent, I still am.
By the way, did you know this:
According to Mario Wiki, 9-Volt got his name because the NES used 9 volts DC as its operating voltage, hence his name!