Use caution when fiddling with source-code on a binary distribution. It's fine to use it for inspection, but be careful when you set out to compile and install your own kernel in such a distro.
The folks who put together those distro images really do work hard for you, "so you don't have to," and they make a lot of tightly-interrelated decisions along the way. If you do not exactly replicate the setup that they used when building your kernel, you could encounter all sorts of rather-baffling problems.
If you know well what you are doing (and I do not mean that insultingly...), you can overcome those problems, but if you encounter them and "you didn't sign-on for this kind of treatment" you can certainly feel ill-used.