I had low expectations for the Wii Wheel before playing a few rounds of Mario Kart at the Nintendo Media Summit. The circular chunk of plastic exceeded my expectations. And that's my advice in life: Expect little and be constantly pleased.
I twisted the small wheel to turn my racer. Gentle movements steered me around the tracks, and the setup was most sensitive if I held it at a 90-degree angle, with the face pointing directly away from the TV. A button pad pushed the B trigger, giving me a bigger target to hop and turn. I reached the other buttons easily.
But the control felt imprecise because it wasn't mounted to anything. I unintentionally dropped the wheel angle sometimes, making the system less sensitive. I don't know why someone would want to buy one of these, and I expect most gamers will stick with other control methods.