I run Gentoo, but I agree 100% with @pk5dark . Gentoo is an excellent distribution for learning the ins and outs of Linux. It allows for a lot of flexibility, which is why I prefer Gentoo over other Linux distributions. But I would never recommend for anyone to switch to Gentoo just to get bleeding edge software:
First, Gentoo requires learning a lot more new stuff than you might actually want to learn. It certainly requires learning more than I want to learn. Ask me how long it’s been since I updated my kernel, and then ask me why. Actually no, don’t ask, because I don’t want to talk about it.
Second, Gentoo requires a fast internet connection and a fast computer for compiling from source every single time you update to pull in the latest software, preferably with enough RAM to allow building entirely in RAM. Ask me how long it took to do a required profile upgrade yesterday, which required recompiling and reinstalling every single package on my system, using a very specific sequence of commands. Ask me how I intend to deal with the 715 config files that now need updating. No, don’t ask, because I don’t want to talk about it .
Third, not all software in the official Gentoo repository is as up-to-date as you might need. For example, right now I have to compile libvips from source if I want to install PhotoFlow, which of course also needs to be compiled from source as it’s not available from Gentoo portage. Also for GIMP 2.9, I have to install glib in the GIMP prefix, because the version of glib in Gentoo isn’t current enough, though usually it is.
If you want to switch distributions to a rolling distribution, Debian testing is a good option. Also think about OpenSUSE Tumbleweed. I think Arch also is a rolling distribution?
OpenSUSE has the nice feature that a lot of cutting-edge packages are already compiled and ready to install, whether you run Tumbleweed or simply keep up with the latest release versions of OpenSUSE. For example see:
https://software.opensuse.org/package/gimp
which shows several options for installing GIMP 2.9.9.