I use Debian, so I have no idea how main distros of ubuntu/fedora/opensuse work, or what versions of things they offer, and how that might compare to Debian tes

I use Debian, so I have no idea how main distros of ubuntu/fedora/opensuse work, or what versions of things they offer, and how that might compare to Debian testing. The nice thing is, though, all that information is freely available if you wanted to compare. I can save you a little bit of time by noting that the criteria for a package being promoted from Debian Unstable into Debian Testing has been honed over the years, and is the reason why a lot of people settle on Debian Testing for their day to day machines: The package has been in "unstable" at least for 2-10 days (depending on the urgency of the upload). The package has been built for all the architectures which the present version in testing was built for. Installing the package into testing will not make the distribution more uninstallable. The package does not introduce new release critical bugs. If there's absolutely positively definitely a version of something you want that's in unstable, but not testing, and you are unwilling to wait a week or two before it turns up in Testing - you can usually just download the package and install it with little risk of conflict (presently or subsequently).