This review would best be written as a pros and cons list, so I will write it that way. I hope it's understandable that way.
Pros:
1. Amazing 3D level design makes for plenty of obstacles and fast-thinking action.
2. GX is faster than most racing games.
3. Stunning graphics.
4. The extra parts make some awesome vehicles.
5. The soundtrack is cool enough, even if it's overproduced.
6. The new Spin Attack is a cool addition.
Cons:
1. The voice acting needs serious work and the voices do no justice to the characters.
2. The difficulty levels are harder than advertised. Take it from a really good game racer.
3. The controls are a little slippery.
4. The character motions suck, especially Pico's.
5. The Story mode has a dumb story.
6. The character videos are HORRID.
Overall, if the crew had focused a little more on these flaws, F-Zero GX would possibly be the greatest racing game ever made.