This is a total cheat, since I haven't yet seen part two and so I have no real authority to speak to parts one and two of Che--I'm going to let The Texas Observer do the talking since they have a very good review that I agree with by half. Since I haven't seen the other half, agreeing by half is the best I can do. The upshot of the review in my thinking is that the movies are good for what they are but this goodness is kind of limited since the scope of the movies are limited. They look at Che's guerrilla work and skip over his attempts at governance, the time during which his most controversial and bloody actions occurred.
Parts One and Two are bookends of the same theme of how to be a guerrilla fighter, the first being how to be a successful guerrilla and the second being how to be a failed guerrilla fighter. Che tried to reduce the art of guerrilla fighting into a manual but I think the main thing he missed in this effort was the fact that revolution is really only possible if the people are ready for it or if you have the army behind you. In Cuba, the people were ready due to the horrible governance of Batista. In Bolivia, Che didn't really find any takers.
Anyway, here's a link to the Observer review and a little taste of the goods, The Man Without a Middle:
Soderbergh has been criticized for leaving out the middle section of
what should’ve been a triptych. That is, he ignores Guevara’s years as
blood-stained bureaucrat in Havana. Can we honestly evaluate Guevara’s
career without seeing him at his worst? If not, does that make Che a fundamentally dishonest film?
Soderbergh has answered this question in interviews by saying he
simply wasn’t interested in showing Guevara behind a desk. He only
wanted to make a “procedural about guerrilla warfare.”
Wondering if this is really a defensible goal, given the title
character’s morally muddled middle history, takes me back to high
school, when I argued about Bonnie and Clyde with my English
teacher. She remembered the pair as thugs and couldn’t tolerate their
being glamorized on film. My basic answer: But it’s a hell of a movie!
You wouldn’t call Che a hell of a movie. It’s too
emotionally disengaged for that. We only really get inside Guevara’s
head when he’s awaiting his execution. He’s in captivity, and in bad
physical condition, looking as woolly as the homeless man that he has
in effect become. But when Guevara accepts smokes from one of his
guards, and comes oh-so-close to talking the young man into letting him
escape, del Toro lets his character’s charisma blaze for the only time
in the film. The young soldier is about to free him, then runs out of
the room as if he’s just realized he’s come face to face with the
devil.