Having owned a 197 there is no doubt that an A500ss is as quick below 80 from a standing start and quicker from a rolling start due to it's torque advantage. TMC better still.
Clio much better ride and handling balance, particulary on bumpy roads. Would like to try a Koni A500 car though.
However on the road you'd need to be either very talented, or crazy to make much of a difference on straights or corners in either car.
On track the Clio has better brakes, adjustability and high speed composure meaning quite a bit quicker.