I think that will be more realistic and great to have the "pitch sound" by hitting the kerb, depending by the speed of the car! In this video can be heard the sound effect I am talking about, the sim is netkarPro. http://www.youtube.com/watch?v=2fnzLm6wLZE&feature=related
Yeah, many sim and nonsim have this realistic sound feature, but in a sim this feature should be a must!