Alfa sold 5700 GTV6s in the USA, only 35 of which were Callaways(less than 1% of production). Callaways were blessed by the factory and were sold by Alfa dealers with the usual Alfa warranty. Callaways had 50% more HP and torque and very little additional weight. They're very rare cars that very rarely come up for sale. In my opinion the best examples - like this one- are six figure cars.