I’ve been using linux for some time now, i would still say i’m quite a noob but i’ve tried different desktop environments, for my experience i found GNOME to always be suited for me, anyway i heard many good opinions on KDE and i would love to try that too, i’ve tried cinnamon before and couldn’t really see myself using it, i’ve seen Kubuntu and looks quite lovely, what’s in your opinion the distro that best implements KDE on Debian or preferably Ubuntu?
IMHO, Debian is not the best choice for KDE, especially if you are on Wayland. KDE is a bit more buggy than GNOME, but bugs are fixed constantly at a fast pace, and Wayland support gets better. With Debian, you are stuck with the old version and have to wait 2 years for bugfixes. Kubuntu would be a better pick since it has interim releases with more recent KDE and also official backports with fresher KDE version.
Yes testing is probably better for KDE, it’s great on workstations if you want a rolling release.