Oh dear. All the comments with regard to GT5 seem to be divided between the PD apologists, who desperately want GT5 to be the game it should be, & those, like all the "professional" reviewers, for example, who see the game as it is.
If the AI has improved from Prologue, it's barely discernible. The AI cars still basically follow the racing line & do not react to your presence unless you actually bump them. They do not do bizarre things like pile into each other the way they do in Shift or SCC, but nor do they interact with you in the way they do in FC, F1 CE, or F1 2010. The way the AI cars interact in F1 2010 may not always be completely realistic, but it IS interactive: for example, if you late brake & dive into the inside, they will react to that & attempt to out-throttle you on the exit. This means there is a sense of actually RACING the AI, as opposed to just driving faster than it. There's nothing like that (that I've seen so far) in GT5.
The first console sim I played was FM 1. I remember the races with the AI as being extremely tough, interactive & "unscripted" - every race unfolded in a different way with AI cars doing different things & interacting with you & each other in an unpredictable way. I'm assuming FM2 & FM3 have built on that further. Every objective reviewer has commented on the fact that the GT series has always had drone-like AI. Unfortunately, KY does not seem to take this as a serious criticism, & GT5 does not seem to offer a significant change in this approach. For me, it remains the single most important shortcoming of GT5.
Until you get to the higher level races the AI isn't really fast. Try a comparable car, I love how they have a new feature for A-Spec called "common opponents" (or something like that) so that you can see what types of cars the AI will be using, so that you can pick an appropriate car.
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