If you like racing sims on any level, you must play this game!
Here is what I like about this game:
Tons of cars
Car customization is mind-blowing
Car damage is implemented perfectly
The racing line/guide
The ability to have custom soundtracks
The graphics
The overall sound
Here is what I don't like about this game:
nothing
In my opinion, this is the best racing sim ever.
Each car in my garage that I race on a consistent basis is a truly unique vehicle because of the customization options available. It is very fun to customize your cars in this game, almost as much fun as racing them.
The driving quide is the best thing to hit racing sims since analog control. I can't see why other games won't copy this in some form in the future. It makes the game so much more accessible if you don't know the courses all that well. Some might say that it is not a pure way to play a racing game, but in my opinion, racing games make it tough to get a feel for actual physics of accelerating and braking, as far as whether or not you are going into corners too fast, and the guide just makes it easier to interpret the feel of being on the course when you aren't actually on the course.
The games soundtrack sucks, but you can have custom soundtracks, so that is a non-issue.
All I know is that after playing this game, I'll never be able to play GT again.