Kinda cool...
To start of, you have the whole of Hawaii to drive about in, its very detailed and very big to drive about in. You buy a car and then the objective is to upgrade that car and buy faster cars to win the more advanced races. The gameplay is similar to most of the driving games out there.
I think what stands out in this game is the detail. It looks really good for PS2 graphics, the cars are so detailed you can even switch lights on and off, put windows up and down, and the cars sound just as they would do in real life.
Sound wise its excellent, I also like the soundtrack, I'm sure you'll find something you like.
Get chased by cops, roam around Hawaii, buy cars, enter races, its all you expect from a good driving game these days. And its got more than enough to keep you playing for a while - I've been playing for a good time now and I'm only 10% complete. Its a decent sized game.
Overall if you like games like the big players in the driving game world (Gran Turismo, Need For Speed, etc) chances are you'll like this too, so give it a try.