Ubuntu Studio is very good quality but it's very general: it covers music as well as graphics and video editing. I was impressed when I looked at it.
I haven't tried Fedora Design Suite, but the fact that the Fedora designers use it suggests that it should be good.
You can compare the software on offer here:
https://fedoraproject.org/wiki/Design_Suite
https://wiki.ubuntu.com/UbuntuStudio/PackageList
One thing to remember is that Ubuntu Studio has the long-term-support option with 5 years' support, while with Fedora you need to update to a new version every year.
You also may be influenced by the GUIs available. Ubuntu Studio uses Xfce and Fedora uses Gnome. It's not a good idea to use Fedora a different GUI, as so many of its configuration tools depend on Gnome - including the graphical package installer.