The Clio 2 has independent rear suspension where as the Clio 3 has a rear beam with trailing arms to which the springs and dampers are attached. The dampers fix to the arm inboard of the hub and mount to the body frame inside the boot. The springs are mounted forward of the dampers on the arms and mount onto the chassis frame.
In terms of the driving experience, the Clio 3 is a more mature drive whereas the Clio 2 is more of a hoot. However, with the standard Clio 3 the suspension is just far too soft to go chucking it as much as you could with the Clio 2. That said, it still handles pretty well for a standard car.
Ive not driven a 1*2 yet but I did get a 197 to myself for near 30 mins out of a dealership and I really think the handling is superb. Its stiff, there very little roll, if any but at the same time, the ride quality is not really any stiffer. If you get what I mean. Over the seriously bumpy roads its quite crashy and thrashy but thats mainly down to the stiffness of the springs.