Forza 3, to me lost it's touch after a month of gameplay, all the cars handle the same, when I say that I mean that 4wd cars all handle the same, Rear wheel drive all the same, Front wheel drive all the same, and even if they are slightly different you can tune them so that they do in the end.
The one thing I love about GT5 is the driving expereince is simply great, I can't compliment it enough, regardless of what ever other flaws present themselves, I really enjoy driving on GT5, drifting is actually an art, not some noob 5 y/o kid jamming his handbrake on, then mashing the accelerater in any gear, in some garbage car he brought that has a cheapo fast and furious paint on it..... from the terrible storefront whic is choc full of ugly paints, which some other guy goes and rates five stars.... oooh man don't get me started...... any who GT5 is simply "better" at driving