I know you can't fully judge physics and handling models from a video but this actually looks OK. The slide at 0:20 and subsequent correction look quite natural, as does the way the car rides the curbs. Sounds seem to have improved a lot from PC2 as well.
Whilst I'll probably pass on PC3 myself, it could provide a gateway into sim racing to someone coming from the Forza/GT crowd (which is how I think SMS are positioning it).