Forum OpenACS Q&A: Re: Debian stable or testing? apt-get or yum? etc.
I run Debian unstable on three different machines (one of them is a server) and only had one breakage in a desktop machine in the last year. The breakage was with GNOME, and was easy to solve.
In the one server I moved to unstable, we were running Woody + backports, but it became too painful. For a while we had a chroot with unstable, just so we could have some sid packages. So we (the group handling the machine) just bit the bullet and went to "careful unstable", meaning we watch the mailing lists and are careful before doing an upgrade.