I really dont see the problem with Punto Abarth derived underpinnings....As Julian said "the Punto drives great".
In a recent test Alain Prost rated the Abarth SS better than the Mini Cooper JCW:
http://www.quattroruote.it/primo_contatto/articolo.cfm?codice=140346
He couldn't be more enthusiastic about the Abarth, giving it's steering, handling and engine great praise. He calls it "un'auto sportiva, davvero molto sportiva"- "a true sports car".
He had some reservations about the Mini though- namely the unpredictable rear end, the driving position and the engine's lack of low down grunt. In the end the Fiat was his clear favourite. You'd never see that result in a UK mag! I'd trust the 3 times F1 champion myself though.
Can't wait for the 230bhp GTA!!