I disagree there mate, Amauri showed he can score in one of the most difficult leagues in the world, while Huntelaar only showed he can score in the Dutch league.
Just look at Kezman, he scored 25+ goals for PSV every year, but at Chelsea, Atletico Madrid and Fenerbache, he failed.
I prefer going for a SerieA proven striker then for Huntelaar if we have can choose.