It would be nice if LWN evaluated Mageia for a while. The 'Rawhide' is called Cauldron. You're expected to follow mageia-dev, as planned changes are announced there (+ after the fact announcement in case breakage was unplanned).
I don't have any major issues running Cauldron, aside from the periodical big changes. For big changes we have an updates_testing channel, to test e.g. new xorg or new systemd. Those are used rarely though.
Packagers not running Cauldron are the exception (though take into account the size of the distribution; Fedora is much bigger).
Note that at the moment I find Cauldron really unstable compared to usual. This due to two big problems; Postfix doesn't start and as we're switching to systemd only, GDM doesn't seem to notice that you logged out.