This isn't Mario Kart.
Whether you're playing the Wii or DS version, MySims begins with its signature requirement of customization. The gives you the freedom to choose between a boy or girl main character, and you have the option of changing basic external qualities such as clothing, skin color, size, and that sort of thing. In addition to your customizable persona, you also have the option of tricking out your car. Of course, there isn't much to do to it given your lack of appropriate funds.
While arcade kart racing is all about having fun with your friends, unless you're willing to brave the less enjoyable single player campaign mode, then you'll hardly have anytime enjoying the game with friends. MySims racing comes with a Story Mode to attempt to make the single player game interesting, but all it really has you do is drive around and do Animal Crossing-style favors for people when you're not racing. The story revolves around the town getting tired of racing, and the need of a new champion would be enough to rekindle the town's love for the pastime.
The unfortunate part of the game is that while it tries its best to separate itself from Mario Kart, it's going to be compared to the game anyway. The Wii version of the game supports the Wii Wheel accessory, and the controls are mostly the same. The DS version of the game has the same button layout, but it lacks depth because the power-slide mechanics are nowhere near as easy to execute as drifting in Mario Kart DS.
As far as the game's look, it's just as colorful as anyone would hope for a family-style game to look. The race tracks are all unique and the really cool thing is that most of them have their own paths and shortcuts. While the shortcuts are more painfully obvious on the DS because of its dual-screen mechanism, on the Wii it's more about noticing the surroundings of your car. The sound is also typical of any Sims game, with nothing but Simglish spoken, sometimes the game is a pain to listen to. The music isn't really anything memorable and doesn't do much to blend with the experience, which is quite unfortunate because the music in The Sims 3 is terrific.
A hardcore kart racer won't find much to like about MySims Racing, but if anybody can get by the fact that it's not Mario Kart, they'll find that this is a game with some good elements and is quite enjoyable despite its lack of polish. As far as a choice between the Wii version and the DS version go, the Wii version is superior because of not only its graphics and sound, but because the controls are more intuitive than anybody would think.