When comparing Slax vs Doudou, the Slant community recommends Slax for most people. In the question“What are the best Linux distributions for desktops?” Slax is ranked 54th while Doudou is ranked 80th. The most important reason people chose Slax is:
Changes you make in the configuration persist if you run from USB.
Specs
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Pros
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.

Pro Modules
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.
Pro Concise "all in one" kid experience
From the pre installed apps to the interface everything about this distribution is dead simple. No necessary set up, just boot and go.
Pro Installable live cd
DouDouLinux comes as a live cd, meaning this distribution can be used on any computer not matter the OS in Live CD mode as well as installed fully onto the device depending on the hardware support.
Cons
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.
Con Based on an old distro
DouDou Linux is based on Debian 5, which is pretty old. So this means the software found in the distribution will be old. This also means the hardware support will be lacking compared to newer based distros. So for those that do want to install it would be a good idea to make sure the hardware is supported by Debian 5 and DouDou Linux.
