Anton,
i agree with the reason with why you wear the shirts, because YOU do understand what he's about. I have asked many ppl why they wear the shirt, or who Che was and they dont know.

as for the "correct" pronunciation Capo, your version is the anglisized(sp?) version.

The way I and the rest of the hispanics pronounce his name is
Che = Chair without the "ir"
Guevara = Gue is pronounced like guess without the ss..... and vara is pretty self explanatory.....

but i say tomato and you say tomahtoe right?