Slackware-current is basically as stable as Fedora is at any given time so it's hard to really discourage its use.
Honestly, Slackware is almost a RHEL/Fedora type ecosystem when just taking about official packages. Slackware-current gets new stuff, Slackware releases only get bug fixes, and not too many of them at that.
I'm not sure I agree with that comparison. Slackware-current will become the next stable release once all of the kinks have been worked out. Is RHEL ever really a snapshot of Fedora?
Basically yes, Fedora is Red Hat getting free testing of features and when it's time to create a new RHEL release, they grab a Fedora release, set it in stone and work from that.
RHEL trees are forked off the Fedora repository, and released after a substantial stabilization and quality assurance effort.
Which adds a quote from the Fedora Project:
Red Hat Enterprise Linux is a commercial enterprise operating system and has its own set of test phases including alpha and beta releases which are separate and distinct from Fedora development.
And on that page[1] it states that RHEL6 is based on a "Mix of Fedora 12 Fedora 13 and several modifications".
Sorry to be pedantic, but that's significantly different than the Slackware model. Maybe it's just PTSD; I fled from RH in the old days onto the path that led to Slackware, so any comparison makes me touchy.
Honestly, Slackware is almost a RHEL/Fedora type ecosystem when just taking about official packages. Slackware-current gets new stuff, Slackware releases only get bug fixes, and not too many of them at that.