Summary: The modding in this game is a lot of fun, but that's the only thing good about the game. Though it tries to be like Mario Kart, the racing itself falls rather short. Too much in this game depends on luck rather than actual skills. Also I've had a really hard time getting enough people together for an online game and on the few occasions that I have managed to, it's always only been the bare minimum of four players.
Summary: Don't be fooled by the cartoon graphics or 7 age rating, even on 'casual gamer' setting the developers reveal they have no idea what a casual gamer is. If you want to do the modding, or play people you know online, this game may be fine. If you want to play the AI, unless you are a callous-thumbed, bleary-eyed, do-nothing-but-play-racing-games-all-my-life kind of person this game will leave you frustrated.
Summary: The game play itself is good. 3 to 4 stars there, well done. The ability to modify things (hence the game title!) is good. Well done. The time spent waiting for the next part to load from race to race, from title to title is laborious and very very frustrating. Shame on you. Hand your stars back please. Bought this as a game to play with my two children. They really like the game but don't have the patience to play it for long.