First of all Che is pronounced Chay (as in chain) and not Shay. This is a splendid historical recreation of the Cuban revolution - with emphasis on the Sierra Maestra period and the seminal battle for Santa Clara. Santa Clara was strategically important because it was exactly in the middle of Cuba and so was the tipping point in terms of rebel control - from controlling the east of the country the rebels gained a foothold in the west by capturing Santa Clara and became unstoppable. Key to their triumph was winning over the peasants and this film confirms this. I notice that Jon Lee Anderson was a consultant. He wrote the definitive biography of Che (warts and all) and his touch is all over Sodeberg's work.
It's by no means a hagiography and Che is often shown as inflexible and even priggish - but his integrity, self-discipline, and clarity of vision shine through. Che was perhaps more direct and brutal in punishing those who deviated from the path of revolutionary righteousness, he summarily shot anyone who deserted. In the film they fudge it by showing those he shot as murderers and rapists as well as deserters. Not quite true.
It's a shame that the film starts in Mexico City after Che has undergone his conversion from upper middle-class Argentinian doctor to revolutionary. His travels in South America (covered in the Motor Cycle Diaries) were only part of this conversion, his experiences in Bolivia (where a revolution tolerant of its erstwhile enemies failed) and in Argentinian politics also shaped his vision.
Benicio del Toro doesn't look as handsome as Che but he has the physical presence to capture the effortless charisma of the character, and this is a virtuoso performance.
Overall a great film - I'm looking forward to Part 2 - not withstanding the tragic denoument.