the best to come out of Germany:
Small Cars: Audi A2/Mercedes Benz A-Class
Small Saloon: BMW 3 series/Mercedes Benz C-Class/Audi A4
Big Saloon: Mercedes E-Class/BMW 5-series/Audi A6
Luxury Cars: Mercedes-Benz S-Class/Audi A8
Coupe: Mercedes Benz CLK/CL
Convertible: Mercedes Benz SLK/SL, Porsche Boxster
Sports Cars: Porsche 911 Turbo/GT3/GT2/
Super Cars: Mercedes Benz CLK-GTR/Porsche 911 GT1
I think every car listed here is near enough leader in their class, with the exception of the Sports Cars to the Italian marques. Judging by this i dont see how any other country can be classed as better than Germany