From what I have seen GT3 delivers the most realistic graphics, physics of the individual cars, and details ever. Here is the run down of the things I have noticed:

• the disk breaks glow red when you slam on the breaks
• you could see the racing "stickers" on the cars
• you could put new rims on the cars
• each car is detailed to to show off the real life counter part (i.e. like the Honda Civic SiR have VTEC on the side, etc.)
• each car feels different, and acts different from each other
• realistic showdow effects, according to where the light hits the car
• each car make their own engine sounds (accroding to what modification you have done for them)

Please make sure to e-mail me on any new "Attention to Details" that you may find. Thank you.