I have a nearly complete collection of Zymurgy and BYO, starting in the mid-90's. Like others have said, lots of info is inaccurate, especially before 2000, but I can't bear to part with them. I like the feel of paper in my hands, too. Online just doesn't cut it, and can we really be sure ezines will be available when stuff like the Zombie Apocalypse hits?
How often do you look at them? That was the deciding factor for me.
More often than you might think, especially the issues within the last five years. Not so much for the older ones.