Excellent
You'll get the best Mario Kart Wii experience by using this. Sure you can play without it and even with classic controller, gamecube controller and a wiimote-nunchuk combo - and yes - you can get better times by using in particular gamecube or classic controller - BUT nothing feels better than playing the game with this wheel. And you need to get more - Mario Kart Wii is a multiplayer thing - you want your friends to share the experience. If you only have the one that was packed in with the game - Get 3 extras NOW - (and extra wiimotes if you still don't have four).

enjoyable
Its amazingly comfortable and it made me feel like im actually driving with a steering wheel.
a must buy for people with mario kart or any other racing game!

Pleasantly surprised
I got this with Mario Kart Wii recently, and instantly got into driving with it. Considering its just a case for the Wii Remote, it doesn't actually DO anything, other than provide a steering wheel shape for you to hole - which makes it that little bit more immersive to play.