As you can see in this video, the controls for Nikudan (Japanese title) are pretty solid. The game doesn't seem to tolerate too many sweeping or drastic moves, but fast jabs and bodyblows seem to register just fine. More arching motions, like hooks and uppercuts, seemed to require slower motions, which sort of squashes the whole "kicking a real dude's ass simulater" effect.
Still, if you couldn't tolerate the relative cuteness of Wii Sports Boxing, this could be a fine alternative for you. The game's black and white filters and grizzled, shiny, pocky faced combatants are sure to fans of grimy, foul smelling bar fights something to crow about.