THE GOOD:#1 Customization is awesome. There's a lot more customization you can do in this one. IE: Scissor doors, split hoods, engine/trunk neon, gauges, more carbon fiber options, spinners, lots of spoilers, rims, colored lights, more vinyls, window tints, side mirrors, wide body kits, purging of NOS at the start with colors and hydraulics.
#2 The dyno tuning. I didn't realize it was that important it was in making racing easier to tune your car to specific settings. I was able to control my car even better when I did this like after 50% of my game.
#3 The graphics are upgraded a bit from UG.
#4 Roaming around the vast city in your car is prety cool. It can get tedious after a while at times. I did get tired of the hilly area of UG2 after awhile.
#5 Extra types of races. New to this one are Street X racing, Outruns, and URLS.
#6 More cars. There was a surprise with having SUV's in this one. I didn't really race with them, because they are so...