Me too amigo, although I prefer civil war SW's to mexican revolution SW's, I'm not particularly fond of either. Its the reason why GBU is my least favorite of the Dollars Trilogy (even though I still love the film hehe).
I like my SW's to have "traditional" western elements. Stagecoaches, cowboys, ranches, saloons, Sheriff's etc.... Also I prefer my westerns to take place in the southwestern part of the US, in the 1870-1890 time frame.
Zapatas don't really have any of that, for example, Duck You Sucker has machine guns, motorcycles, tanks, and also features an urban setting. This is not really a "true" western in my opinion. I'm not saying I wouldn't watch these films, surly Companeros, Mercenary, bullet for the general were fine films, but just not my cup of tea.
My favorite type of western is the "lone stranger" type.