I've tried 3 different, one black (looks like the one rjvznl posted tho black and lose), one similar to official but weights less (with only 2 linked plastic to the circle) and the official wii wheel (which has 3 linked plastic to the circle)
and I can't really say which is best, but I think I like the official cause it gives a bit more weight. The black one didn't have an opening so u could use the wiimote sensoring.
oh and another thing, I always play manual while my friends play always automatic. it's cheaty to play automatic cause you turn much easier than the manual. even if u were and expert to take turns in good ol double dash u suck in mk wii cause the automatic just is superior. (except u don't get the red boosts from the turning)