A McLaren F1 would last on some parts of Pikes Peak.
In 1 corner, a few years ago, a driver came around the turn, but his front right caught the part where the hill started to go up, and ended up in causing him to try and slide back into the turn. Instead, he drifted off the course in a bank, and slammed into some trees. Only good and bad news. Good, the trees kept from going near the cliff. Bad, he died on impact of the trees.
The point is, the part he was on, was more of a soft dirt part. Yes, I feel sad, and I'm sure you do to.
Anyways, what was said above earlier, I agree. The courses ALL felt like you were driving on hard compact dirt that seemed more like tarmac with some harden dirt on it. You're tires never really hit something soft. You're car never dipped on a straightaway unless it was a bump, or a curve. I hope that changes in GT4.