As involving as career mode is, the rawest fun comes from the unique Trans World Cup, which also happens to be the mode best suited to racing on-the-go. Here you'll blow through a taster's choice of events across fifty-odd tracks. Some are straight races, but the most fun are variations like "Bring it Home," which starts you out at the halfway point in a damaged rig, or "Show Off" contests that encourage power slides and air time.
The physics system completes the illusion, asisted by convincingly gritty audio, but it does exhibit some subtle lag. This makes cars feel more slippery than they might otherwise, and it’s a little disconcerting to get rear-ended and see damage take effect a split second later. There's also the usual racing simulation bugaboo: drag a wheel or two in the grass, and you'll feel virtually no ill effects.
Once you're tuned to these quirks, and using the PSP's analog nub in a more sensitive manner - don't expect to get away with flicking it from one extreme to the other - these things fade from prominence. A "flip screen" option should keep southpaws happy, and three different profiles can save to a single memory stick. Up to twelve players can compete via (mostly) smooth wireless with only three copies of the game, thanks to disc sharing that lets up to four people use a single UMD.