I've been buying some cars and driving the nordschleife to try to find what's different with the ai. Imho they drive exactly like they have always been.
Still extremely slow in T1. Still waving left and right on the straight after fluhplatz. Silly slow in aremberg, you can pass 4 cars easily on the outside. Still brake checking and going slowly on that next straight. Braking really early and going slow through adenauer forst and brake checking on the corner exit out of adenauer section. And so forth. The ai still hits you exactly the same way in the exactly same places. Like when going into kallenhard hairpin. There literally is no change. I think the claim of ai change is bs. Or has to do something with the coding and efficiency or something that isn't possible to see from driving perspective.
I've seen no evidence of it. I've done hundreds of laps around nordy racing the ai cars in arcade and single races and I am totally unable to find even one single difference. In fact the ai drives so similarly every lap that any kind of change would be easy to spot.
Forza feels as though it has almost zero weight transfer, and the replays only make it seem even worse.
In terms of car handling I much prefer gt5 over forza3, but of course arguing that either is particularly accurate as a simulation would be stupid. If gt5 didn't do stupidly big jumps in a ridiculous way it would be much more worthy of a "sim" tag, though.
Forza has pretty much no lift off oversteer and the cars are glued to the road with how numb and stiff the cars feel, They all handle like the suspension is 5x too hard then they understeer off the road because the steering aid wont turn the wheel as much as an analogue controller wants, Which is easy to see when using cockpit view...
T10 even said they were dumbing down the Sim aspects to make it more accessible to people that have no interest in Sims, i.e. cripple its sim like edgy driving that had potential in FM1. FM2 feels a better sim than FM3 lol.
Even watching comparison vids u can see FM3 is a numb glued to road arcade racer, No camera shake, no twitchy opposite lock etc etc even in powerful rwd's.. Every vid of FM looks like they are using full assists even when the dash say there r not lol.