Korda died not long ago - and as I recall - in the obits it was noted that he used Tri-X for the shot.
Hey, when you need basic B&W - go with the best!
There was a showing at ICP a while ago that displayed the "progression" of this photo from an original news-like pic to a "glorification" of a dead revolutionary to a 1960's and 1970's lithographic icon and on to a current day advertising brand!
Right now they mainly use the image on T-shirts and stuff. But one more generational turn and it will be possible to use Korda's "Che" on a mainstream brand item and it will rival the Coca Cola signature!