Well I’d certainly rank them in quality according to their time of production: 1. The Mercenary; 2. Companeros; 3. What am I doing in the Middle of the Revolution. However, I still really like the third one and think that most of it is very well made indeed with good production values.
As for the bull and the car scene, it is so weirdly filmed that I wonder if Corbucci did it for comedic effect rather than laziness.
I also really love the way Corbucci weaves real historical figures into his trilogy. This one has Herrero, Carrasco and even features Giuseppe “Peppino” Garibaldi flying all over the place in a biplane.