Excahnge is a bear to administer. All but the smallest organizations should probably have a full-time Exchange admin if they're planning to run it. And even then, scheduled downtimes in the neighborhood of once per week seem par for the course.

Compare that to running sendmail or postfix or exim or whatever MTA you might use plus Cyrus or whatever IMAP server you want to use (I chose IMAP as an example since it most closely resembles Exchange's features) probably requires the occasional attention of whatever Unix admin you might already have.

Not to mention the fact that Exchange, much like any other MS product, is pretty much a black box, even to the administrators, so that the equivalent of reboot and reinstall is one of the major troubleshooting methods.

I use Pine, too, including PC-Pine. I have ever since I fell in love with IMAP and had to switch away from mh. Occasionally, it is nice to have a nice GUI for the very occasional task, and Pine's lack of real threading is a serious drawback, but otherwise, I'd seldom rather use anything else. Apple Mail.app runs a close second these days, though.