Advantages: Large amount of Free Software packages available, fully free according to the Free Software Foundation, stable, rolling release.
Disadvantages: Parabola does not offer any non-free software, so you must make sure your not dependent on that. Parabola does not have all software in their own repo's. Arch's repo's need to be enabled.
Personal experience: I've distrohopped for 3 years. Parabola stopped this habit, because it has everything I want.
Use case: I mainly use my computer for web-browsing, programming and watching video's.
Setup: I run the Awesome Window Manager with custom scripts to boost my efficiency.
I followed the recommendations of the Free Software Foundation which lists the following GNU/Linux distributions as free according to their definition of freedom: blag, Dragora, dyne:bolic, gNewSense, GuixSD, Musix, Parabola, Trisquel and Uto Ututo. I tried most of them. I even bought computers pre-installed with Trisquel from ThinkPenguin and The Ministry of Freedom (minifree.org). I was able to install the version of Parabola GNU/Linux which includes the Mate desktop. It works fine but the amount of data for the updates is very high. I estimate that there are about 100 MB to download every day with th all the packages I have installed.
I wish I were more competent to install just the Parabola base install and then just the i3 tiling window manager, emacs, w3m, lynx, surfraw, mpd, mpc, gnuplot, matplotlib, python, ...