In before steams evil, steam sucks, steam is DRM, I hate steam, i hate dow2 'cause it's on steam, I wanted to get dow2 but I won't because it's on steam, I won't get this because it's on steam. Did I cover everything?
It's free for everyone. Speaking as someone who hasn't played the game, though, it's not particularly interesting to listen to. Fairly generic orchestral bombast. It's well-done generic orchestral bombast, but it's the sort of thing that only really works in the context of the game. I mean, I assume it does, since I haven't played it. Also, the credits track has the best title in the history of videogame music.
I'm rather enjoying it. Out of the tracks I've heard so far, the highlight for me is either To Battle Brothers or Show Me What Passes For Music Among Your Misbegotten Kind