Ranked in these QuestionsQuestion Ranking
Pro Persistent changes
Changes you make in the configuration persist if you run from USB.
Pro Pretty fast to boot up
It was considerably fast to turn on when booting from cd.
Standard tar archives plus some simple shell scripting produces modules that you can load dynamically into the OS for added apps and functionality.
Pro Modern desktop
Pro Small footprint
About 200mb, but with a full KDE4 environment and loads of useful apps.
Con Overly complicated HDD/SSD installation
While it has a nice layout Slax's lack of an installer tool like Tinycore's just can't be justified. It seems strange that it comes built in with programs that some users may not want, yet it doesn't have an easy way to install it. Due to its heavier use of RAM, built in software, and lack of an installer its hard to choose it over TC.
Con Works slowly on old computers
Con Infrequent releases
Since Slax is maintained by only one person, releases are not that frequent. So it may take a while to get bug fixes or new features once you start using it.