AFAICT Tumbleweed would be closest to NEON, where KDE is concerned. Tw usually has released versions within 24 hours. Krypton uses the KDE:Unstable repos, where Neon, again AFAIK, uses latest stable KDE releases.
Yeh KDE Neon has two versions. Developer which is unstable and User which is stable. I use the stable version.
So for Tumbleweed I keep stumbling across cautioning in regards to Nvidia drivers. I am not familiar with how openSUSE does it but I noticed that OpenSUSE has a one click install option. Does that just add a repo/ppa that installs and updates the driver?
The first one installs the recommended packages, the second a specific packages. Don’t have NVIDIA stuff anymore, but I know that just adding the repo and ‘zypper inr’ will do the job too. If an update doesn’t work, simply boot the previous kernel.
Keep in mind that Tumbleweed is rolling.
Neon uses the newest stable version of Plasma but is based on a stable OS (Ubuntu 16.04 at this time)
The only thing they have in common is that they both have the newest stable plasma version.
Personally I don’t think you can compare Tumbleweed with NEON.
That does not mean off course that Tumbleweed is a bad decision, it is an excellent distro.
But something to keep in mind