I have been using Tumbleweed for a few years now, but while it seems like a stable rolling release distribution, I am not quite sure about the "rolling release" part. Each month, a new snapshot comes out, which upgrades every single package you have installed, regardless of whether there were actual upstream updates. With a full Texlive installation and just a few more suites this amount to roughly 10,000 packages and over 5GB that need to be downloaded and installed each month. This a) kind of defeats the rolling-release aspect for me, b) takes a few hours, and c) feels like a cheat for the sake of stability.

Between those snapshots you might have bleeding edge updates for all the packages, but even then I do encounter package conflicts way too often. Well, on the upside, at least they are detected.

So yes, it is stable, but it comes at a price.

Apart from that, the community support felt mediocre, at least a few years ago. The most visited platform was a bulletin board forum with very little interaction. When I had trouble installing KDE, it took a few days until someone suggested the correct diagnostic tools. This is bad for being the testbed of a commercial distribution. In the end, I just installed Arch, which packaged KDE better than Tumbleweed did.

But on the other hand, maybe only if you use a distro long enough, you get to see the downsides, and each one has them.