
I'm kind of the opposite. I like branching storylines for some games, but I tend to prefer a clearly defined story and objectives. Sometimes I'll make the "wrong" choice in certain games and feel I was cheated out of a better experience. I know cheated isn't the right word, but I like to know I got the best version of a story possible.
Now I have yet to play ME or KOTOR and wouldn't mind so much in those games, since the focus is so heavy on choices. But I find some games punish you for odd reasons based on choices that seemed more or less irrelevant at the time ...