Kindle. I read it quite slowly, resisting getting to the climactic battle as much as Hemingway did. I found it much easier to approach than his Old Man and the Sea, which I started but didn't get far with a few years back, making me think that that might be a gatekeeper suggestion, keeping the casual reader from the man's better works. He's definitely on the romantic and doomed side of things even as he writes unsentimentally about the Spanish Civil War. The structure is straightforward; he's not bothered with playing tricks with points of view, so it's very easy to follow in time, space and character. Given his reputation I was surprised at how strongly drawn his female character(s) were. I wonder what he would have made of present-day USA.
The Wikipedia page has loads of details. The Russian Karkov trashes the POUM, which George Orwell fought for. I think I'll give the movie a miss.