I have a ps3 with gt5, but I still think forza 3 shits all over it to be honest.
Realistic? Bought an exsige and decided to take it for a whirl round laguna secs, only to find I'm getting masses of torque oversteer, yes, that's torque oversteer on THE best handling car in the world, but yet the same track with a rear wheel drive TVR Tuscan S, massive understeer! Plus let's face it, the graphics are pretty damn awful unless you buy one of only 200"premium" cars, the other 800 are imported from gt4 and look damn awful...
Even after all that forza wins hands down just for the unlimited possibilities to make your car(s) totally unique with 20 graphical layers.
Ladies and Gentlemen, our first SuperHero TTFer