Benefits of Slackware
I'm quite fond of Slackware.
It seems to be the only Linux distro out there which includes the devel headers in every package. And why not, they're tiny? Yet all other Linux distros insist on keeping the devel headers away from users, imposing a massive barrier to entry on users who first decide to try compiling some software from source. No idea why that's so novel in the Linux world... All the BSDs include devel headers like Slackware.
And no dependency nonsense. If I compile some library from source, I can still install binaries that depend on it, without a ration of crap from the packaging system's dependency tracking. And the worst part? Those packaging systems won't bother to check and tell you when the contents of an installed package have been removed/corrupted/etc. They can find out with a single command, but they don't really care to keep track of your system, just a database that says X is installed, so you can go on your way. Bah!
I don't use Slackware anymore, just because if I've got to use Linux_X at work, it saves my brain so many cycles to use Linux_X at home, too. Slackware may be less of a hassle for me, but if I've got to put up with a set of hassles anyhow, I might as well limit myself to the one single set of them.
Slackware's style comes with some downsides, too, but it's a great system to learn Linux on, and I don't mean just install and blindly use it (ala Ubuntu), but to actually learn the gritty details of how Linux works.