I usually switch to testing about 1 year after the release of stable. We’re about the 9 month mark and I’m getting anxious. Any major issues running testing? This is for my main desktop.
I would say testing is okay - I have used the same install on my desktop continuously since early 2022. It’s the same as usual - some packages might disappear during transitions and then reappear, like FreeCAD. When that happens, I just use the Flatpak. I think the only major issue I’ve run into with current testing was some of my systems got borked during the time_t64 transition and I had to chroot in and fix them, but that got sorted out months ago and is probably the only huge issue I can think of.
Running unstable/Sid is usually pretty stable.
Most of the time I use the priorities and pinning to run a mix of testing and unstable (certain bits from unstable gnome I ran from unstable). I don’t ever remember it having a problem in years.
You’re very safe with testing.