That's interesting Peter, I wonder if that increased stiffness at the front is why the steering feels a bit more positive.
I think there is more to it than that. The S1 to S4 cars have chassis that was originally designed as a track car. As a road car the lack of ARBs and other quirks made the steering a bit different, despite the springs and dampers being revised for road use.
The S5 has a much more conventional front suspension, with an ARB, upper and lower wishbones. The additional tub stiffness allows the suspension to work better and more importantly like other fast road cars.
