Some quotes from the Autocar road test:-
The 500's chassis used to be its weakest link, a choppy ride and rather ordinary handling a disappointing contrast to the polished appeal of the rest of the car. But with the debut of the 500C in July last year came some suspension changes, mostly affecting the rear axle, which have done much to civilise this baby Fiat. The sudden, occasionally bouncing progress – particularly acute aboard the Sport – has mostly been banished, and small bumps are absorbed without much turbulence reaching the cabin.
Also improved is the Fiat's electric power steering.
The 500 handles better now, too. It feels far more settled with the reduced bounce, and that encourages you to corner harder, as does the crisper steering.