I've been running on stable for a while. I've been considering switching to testing (looks easy according to this thread) but I don't have a good handle on how much I could expect in the way of instabilities or other issues.

Anyone have any thoughts as to which of the two dists would be the most stable, and secure, on a production server? (Assuming of course it it kept up to date on a regular basis.)

I wouldn't usually recommend testing for a production server (although i use it on my desktop), for two reasons:

* Things do break badly every now and then, although this tends to be in big complicated things like gnome, which you probably aren't running.

* It doesn't (usually) get security updates - vunerable packages can hang around for ages.

However, as sarge is moving towards becoming stable, it is currently getting security updates, and things are (slowly) beginning to become a bit more static. You might consider tracking it from now until it becomes stable (this is what I'm doing on my linode). Be prepared to do a lot of apt-get upgrading though.

Since you're looking for stability and security though, a better option might be to take a look at somewhere like http://www.backports.org/ or http://www.apt-get.org/ and use more up to date versions of key packages on the stable distribution if you really need the new features. Remember one of the main advantages of debian stable is that it really is damn stable.

I actually run unstable on mine. Probably not the 'smart' thing to do but I haven't had any problems with any of the services so far.

Just always try to keep updated on your unstable programs and run update with a wery eye It could break your stuff.