Recs.
Updated
SpecsUpdate
Pros
Pro Full control of the software
You build the package from a source you can see and read. You decide which features you want to build in and which aren't needed. You can choose build options, optimisation and whatever else fancy stuff you want modified. With a binary distribution this simply isn't possible.
Pro Great for anyone who is serious about learning the intricacies of Linux
It's useful for both beginners and professionals. For the installation, Gentoo offers various types, which are referred to as stages. Basically meaning how in depth you would want to go into the process of installation. For beginners it's useful to choose for a starting distro due to its various stages that can be very time consuming but beneficial as you learn the composition in general of Linux.
Cons
Con Not beginner-friendly
You have to read a lot of instructions to start, even if you are familiar with Linux. Furthermore, as you have the ability to configure the kernel and init system, though you are not required to and can use other options, you might experience some boot failures at the beginning.