Being a Game Boy Advance title, Hot Wheels Velocity X sports miniscule, isometric-view graphics of the popular tiny cars in action. For all gameplay purposes, the viewpoint works fine and the tracks are nicely detailed with little environmental touches (trees, snow, signs... stuff like that). The coolest visual aspect of the game comes when you hit a corkscrew or spiral ramp; the screen moves at a blinding pace while the car careens through the turns in 3-D, and then it's back to racing as usual. Other than that, you'll never see anything groundbreaking in this one.
There's nothing to write home about in the audio department, either. None of the tunes are memorable, and while the engine and brake noises are pretty well-crafted, it's all just a bit too repetitive to leave turned up for hours at a time. Sometimes the cars will produce a revving sound when simply entering a corner or driving in a different direction, when there's no change in speed or letting off the gas. It's very strange and slightly annoying after a while, but, oh well.